21000+4004 KUI 103     Astrometric orbit by Lippincott (1975), with only the semi-major axis   Lip1975 
                       derived from visual separations. The longitude of periastron has been           
                       reversed to correspond to the visual position angles.                   Lip1975 
                       An observation by Tokovinin (1982) - 1981.370, 48.1 degrees, 0".377 -   Tok1982a
                       was reduced improperly, so has been removed.                            Tok1982b
                       Visual primary is a BY Dra-type variable, and 3.3d SB2 (#1280 in                
                       Batten et al., 1989).                                                   Bte1989 
                       Pourbaix gives combined solution for this resolved SB2, yielding        Pbx2000b
                       orbital parallaxes and component masses.                                        
                       See Baize & Petit (1989) catalog of doubles with variable component.    Baz1989d
                       GJ 815. In addition to the component that we resolve with AstraLux,             
                       which was previously known and has been studied over a long timescale           
                       (e.g. Lippincott 1975), the primary component of the resolved pair is   Lip1975 
                       a 3.3 day spectroscopic binary (Pourbaix 2000). Estimated age 30-300            
                       Myr; masses 0.58 +/- 0.05 and 0.26 +/- 0.09 Msun; a ~10.5 au.           Jnn2014 
21001+2555 GRV 401     BC: Also known as GRV 402AB.                                                    
21001+0731 KUI 102     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 3.08 +/- 0.94, 3.20, and 1.40 Msun, respectively.             Mlk2012 
21003+3543 SEI1361     SEI1362.                                                                        
21004+3426 FAR   1     SKF 321. Primary is DB white dwarf GD 392. Comparison of POSS I and II          
                       plates indicate FAR 1 comprises a common proper motion pair                     
                       (pm 0.17+/-0.01 "/yr at 44+/-5 deg). Spectroscopy and multi-color               
                       photometry indicate companion is a DC white dwarf. Assuming a log g             
                       value for the primary of 8.0, distance is about 57.8 pc, masses ~0.59           
                       and 0.153 Msun, and T_eff 11,625 and 3,509K.                            Far2004 
                       Primary is white dwarf WD 2058+342 = GD 392.                            Far2005b
21005+1920 BU 1497     B is BD+18@4674.                                                                
21006+5432 HJ 1606     Also known as VBS  33.                                                          
           HJ 1605     Original C component of HJ 1605 = HJ 1606A.                                     
                       WDS designation of HJ 1605 changed from 21003+5430,                             
                       HJ 1605AC --> HJ 1605AD, HJ 1605AB --> HJ 1605DE                                
21006+1449 BPM2309     [PM2000] 2437142 + [PM2000] 2437114.                                    Gvr2010 
21007+3353 BUP 222     G211-005. None of the OSO components are common proper motion                   
                       companions, based on comparison with POSS2 red plates. Also, the B              
                       component is not confirmed using their data and images from the                 
                       Digitized Sky Survey.                                                   Oso2004 
                       AC: Optical pair, based on study of relative motion of the components           
                       using the method of apparent motion parameters.                         Kiy2008 
           OSO 138     Further analysis shows that Osorio et al. did not take into account             
                       the very high proper motion of the A component. Their AF pair                   
                       corresponds to Burnham's AB, while their AG pair is the same as Opik's  Bu_1913 
                       AD. (note added 10/2004)                                                Opi1927 
21007+2844 BRT  54     ADS 14537, MLB 486 is the same star.                                            
21008+4635 BU  156     Also known as HDS2994.                                                          
21008+3940 SEI1364     ALI 1152.                                                                       
21009+5929 MLR 241     No significant movement since first resolution.                         Drd2009 
21009+1552 BPM2310     [PM2000] 2437811 + [PM2000] 2437977.                                    Gvr2010 
21011+3315 JNN 288     BC: Originally 21013+3314 JNN 288, but found to be B component of               
                       21011+3315 LDS1049.                                                             
21011-4426 HJ 5238     B is CD-44@14241.                                                               
21012+4609 STT 426     60 Cyg. A is probably a spectroscopic binary, and is the variable               
                       V1931 Cyg.                                                                      
21012-3511 TOK 344     A is astrometric and SB, no SB orbit. Tokovinin & Lepine (2012): B is   Tok2012c
                       white dwarf candidate.                                                  Tok2014d
21013+3554 SEI1368     ALI 210. Ali observation in 1933 indicates a large change. Proper       Ali1955 
                       motion or error in one measure?                                                 
21013+3314 JNN 288     G 187-14. Estimated age 1000-10000 Myr; masses 0.24 +/- 0.08 and 0.18           
                       +/- 0.06 Msun; a ~2.4 au.                                               Jnn2014 
21013-3215 RST5475     gam Mic                                                                         
21014+2043 JNN 289     LHS 3610. Estimated age 1000-10000 Myr; masses 0.25 +/- 0.04 and 0.13           
                       +/- 0.02 Msun; a ~8.9 au.                                               Jnn2014 
21017+1652 BPM2311     AB: [PM2000] 2440174 + [PM2000] 2440516.                                Gvr2010 
           BPM2312     BC: [PM2000] 2440516 + [PM2000] 2440753.                                Gvr2010 
21019+2340 COU 128     This object was misidentified as HR 8059 by McAlister & Fekel (1980).   McA1980b
21022+1426 A  1688     Close, rapidly moving binary. Too close at times and quadrant always            
                       uncertain.                                                                      
21022-3128 LDS 731     LDS5916.                                                                        
21022-4300 DUN 236     B is CD-43@14327.                                                               
                       SHY 788. Bayesian analysis by Shaya & Olling (2011) indicates very      Shy2011 
                       high (near 100%) probability pair is physical.                                  
21023+3931 H 4 113     H IV 113. B is BD+38@4320. Also known as STF2748.                               
           SMY   6     AD: Based on his magnitude estimates, the 1875 Ward measure attributed  Wrd1876 
                       to EH was more likely AD.                                                       
           WRD   4     AG: Ward's 1875 EG measure doesn't correspond to any likely companion,          
                       but given his magnitudes, the measure was probably between A and a              
                       companion now labelled as G. The old EG pair has been removed. The              
                       WRD 4ED should more appropriately have been designated SMY 6ED, but             
                       will not be changed, in order to minimize confusion.                            
21024+3739 STF2747     NLTT 50404/50405                                                        Chm2004 
21024+2748 TOK 345     A is ER Vul, W UMa-type eclipsing, X-ray source, SB2E, P=0.698d. Third          
                       body around ER Vul is suggested from (O-C) period, ~30yr?               Tok2014d
21025+1606 BPM2313     [PM2000] 2442264 + [PM2000] 2442031.                                    Gvr2010 
21028+4551 BU 1138     Called a spectroscopic binary in BSC. This may be due to motion in the          
                       close visual pair.                                                              
                       AB: Additional notes may be found in Muller (1955).                     Mlr1955c
                       AC: Optical pair, based on study of relative motion of the components           
                       using the method of apparent motion parameters.                         Kiy2008 
           KUI 104     CD: C is at 21 02.6 +45 53. CE is optical.                                      
21028+3534 SEI1375     Coordinate confusion led to mislabelling of some components. The BTG 6          
                       AD pair was actually BD, the BTG 6 AE pair was actually BC.                     
21029+1708 BPMA250     [PM2000] 2443474 + [PM2000] 2443895.                                    Gvr2010 
21030+1529 BPM2314     [PM2000] 2443644 + [PM2000] 2443653.                                    Gvr2010 
21031+2929 OSO 139     G187-018. AC and AD are not common proper motion pairs, based on                
                       comparison with POSS2 red plates                                        Oso2004 
21031+1434 A  1689     OL 131 is identical                                                     Hei1980a
21031+0132 STF2744     A premature orbit has been computed.                                            
21032+1305 SLE 513     Error in Soulie (1986) measure due to typo in coordinates of primary .  Sle1986a
21032+3645 SEI1380     AB = 21028+3645 HLM  38AB.                                                      
           WAL 134     AC; WDS designation changed from 21028+3645 due to merger of SEI1380            
                       and HLM  38.                                                                    
21032+1305 SLE 513     Large change in separation over 21 years                                Los2005 
21033+1259 HJ  272     Rabe measure: 1913.76, 259.6, 25.92", 9-10 later associated with        Rab1923 
                       21023+3931 H 4 113AC.                                                           
21034+1508 BPM2315     [PM2000] 2444745 + [PM2000] 2444538.                                    Gvr2010 
21035+5925 MLR 243     Algol (EA) type eclipsing binary, P = 9.9634 d.                         Zas2011 
21035+2400 HO  281     A is the irregular variable DY Vul.                                             
21036+5358 ES 2704     B is BD+53@2541.                                                                
21037-0258 J  1717     J  1780.                                                                        
21038-4041 RSS  37     This previously uncataloged double star was a Hipparcos double entry            
                       system. The first measure is determined from the individual positions           
                       listed by Rousseau et al.                                               Rss1996 
21039+4138 STTA214     AB: HJL1104.                                                            HJL1986 
21041+0359 TOK 371     First resolution; estimated period 10yr. Pair is on the Keck exoplanet          
                       search program.                                                         Tok2013b
21041+0300 WSI   6     AB: The 1yr SB with large acceleration has been resolved with speckle.          
                       However, we cannot exclude that it is a triple system.                  Tok2012a
                       Horch et al. (2012) confirm that the known double is comprised of at            
                       least one additional star. Object is a known SB, with period 378 days           
                       (Latham et al. 1992). Metal-poor ([Fe/H] = -1.01). The wider AB pair    Lat1992 
                       has an estimated orbital period of 20 years; Jancart et al. (2005)      Jnc2005 
                       confirm the spectroscopic period with their astrometric orbit of the            
                       inner pair.                                                             Hor2012b
           DSG   6     Aa,Ab: For the Horch et al. (2015) combined solution, spectroscopic             
                       elements are fixed to those of Latham et al. (1992). Assigned spectral  Lat1992 
                       types for Aa, Ab, and B are F9V, G9V, and K0V; derived masses for Aa            
                       and Ab are 1.12 and 0.82 Msun.                                          Hor2015 
21041-0549 MCA  66     Aa,Ab: 12 Aqr.                                                                  
                       A measure on 1980.7257 was incorrectly attributed to HR 8059 by                 
                       McAlister et al. (1983); it actually belongs to ADS 13944.              McA1983 
21042+3542 SEI1387     ALI 213.                                                                        
21042+1558 BPM2316     [PM2000] 2446963 + [PM2000] 2446899.                                    Gvr2010 
21044+4646 DAL  49     Pair mistakenly observed by Daley (2002) for 21046+4627 BRT1140.        Dal2002b
21044+1625 BPM2317     [PM2000] 2447442 + [PM2000] 2447410.                                    Gvr2010 
21044-1951 FIN 328     eta Cap = 22 Cap.                                                               
                       Spectral types and masses of components assigned by ten Brummelaar et           
                       al., based on adaptive optics observations.                             TtB2000 
                       Ruymaekers & Nys (1955) noted discrepancies in the orbit of Zulevic     Ruy1995 
                       (1993), so calculated orbital elements from the Thiele-Innes elements   Zul1993b
                       originally given.                                                               
                       This system has a Delta m of about 1.7 +/- 0.7 magnitudes, as                   
                       determined from lunar occultation measures (Evans & Edwards 1983).      Evn1983a
                       Masses and bolometric magnitudes are derived for the two components             
                       of this system, based on assumed spectral types and available                   
                       parallaxes.                                                             Msn1999a
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 2.91 +/- 1.61, 3.24, and 3.25 Msun, respectively.             Mlk2012 
                       Docobo & Andrade (2013) derive a dynamical parallax of 19.49 +/- 0.29           
                       mas and component masses 2.03 +/- 0.12 and 1.21 +/- 0.07 Msun (for              
                       spectral type A5V) or 20.46 +/- 0.32 mas, 1.75 +/- 0.11 and 1.05 +/-            
                       0.06 Msun (for A3IV). See paper for extensive notes on this system.     Doc2013d
21045+2350 POU5130     Aka POU5124.                                                                    
21045+0746 BU  269     H 1  62.                                                                MEv2010 
                       BU 835. H I 62 probably same star with an error of 10@ in declination.          
21045-4615 TOK  35     Period of visual pair ~85,000y.                                         Tok2006 
                       A is SB2, P=19.698d                                                     Tok2014d
21046+3345 CXT   1     ROE  53 or J 3123.                                                              
21046+1400 BPM2318     [PM2000] 2447922 + [PM2000] 2448172.                                    Gvr2010 
21046+0530 BUP 223     3 Equ.                                                                          
21047+1152 MLR 541     Also known as HEI 405.                                                          
21047+0332 SE    3     Aa,Ab: This is called AD in the Greenwich Observations. The measures    L__1895a
                       are probably of BC.                                                             
21048+3545 SEI1392     J 1153.                                                                         
21048+3531 S   773     B is BD+34@4265.                                                                
21048+1506 BPM2319     [PM2000] 2448398 + [PM2000] 2448470.                                    Gvr2010 
21049+1549 BPM2320     [PM2000] 2448685 + [PM2000] 2448769.                                    Gvr2010 
21050+1243 STF2750     A,BC: HJL 290.                                                          HJL1986 
21053+0704 ENG  80     AB: Optical pair, based on study of relative motion of the components           
                       using the method of apparent motion parameters.                         Kiy2008 
21054+1139 BPM2321     [PM2000] 2449963 + [PM2000] 2449716.                                    Gvr2010 
21054+0557 BUP 224     4 Equ.                                                                          
21056+1443 TDT2738     CD: Originally 21056+1442 TDT2738, but primary found to be C component          
                       of 21056+1443 HEI  78AC.                                                        
21056+1133 BPM2323     [PM2000] 2450497 + [PM2000] 2450364.                                    Gvr2010 
21056+1113 BPM2322     [PM2000] 2450385 + [PM2000] 2450183.                                    Gvr2010 
21058+1432 LDS1050     AC: NLTT 50497/50489                                                    Chm2004 
21059+0803 OSO 140     G025-017. Not a common proper motion pair, based on color               Oso2004 
21060+1443 BPM2324     [PM2000] 2451551 + [PM2000] 2451691.                                    Gvr2010 
21061+0217 RST5476     BAL 1578.                                                                       
21063+1824 BPM2326     [PM2000] 2452405 + [PM2000] 2452242.                                    Gvr2010 
21063+1233 BPM2325     [PM2000] 2452281 + [PM2000] 2452299.                                    Gvr2010 
21064-4123 SEE 437     eta Mic.                                                                        
21064+1336 SLE 523     Soulie (1986) measure in error, apparently due to typo in coordinates           
                       of secondary.                                                           Sle1986a
21065+2655 COU 527     There is another pair in the field: 1905.93, 285.6@, 79.24".                    
21066+4739 ES   32     63 Cyg.                                                                         
21066+3623 SEI1405     ALI 214.                                                                        
21067+3715 SEI1406     J 1079.                                                                         
21069+3845 STF2758     61 Cyg. According to R.G. Aitken, this was discovered in 1753 by        A__1935f
                       Bradley. Premature orbits have been computed for AB. This is an         Bdy1832A
                       example of a binary known by its common parallax and proper motion              
                       rather than the orbital motion, which has completed approximately               
                       one-sixth of an orbit in the past 200 years. The extremely large                
                       proper motion of this pair has led to some confusion in identification          
                       of others stars measured relative to the primary. Precise epoch-2000            
                       coordinates and UCAC2 catalog cross-identifications are listed below:           
                           A = UCAC2 50084730 = 2106539+384457  pm = +5328 +3258                       
                           B = UCAC2 50084732 = 2106552+384431  pm = +5267 +3143                       
                           C = UCAC2 45407969 = 2106142+383502       +007+006                          
                           D = UCAC2 45407870 = 2105597+384133       +002-006                          
                           E = UCAC2 45408060 = 2106306+384532       +012-007                          
                           F = UCAC2 45408067 = 2106322+384246       +019-002                          
                           G = UCAC2 45408111 = 2106413+384325       +000-002                          
                           H = UCAC2 45408157 = 2106502+384551       -004-006                          
                       The Aa pair was renamed AF. The G and H components were both initially          
                       believed to be the C component. B is BD+38@4344.                                
                       AB: Statistically the same parallax within the errors would indicate            
                       the components are physical.                                                    
                       AB: H 4  18.                                                            MEv2010 
                       An estimated mass has been used by Josties (1981) to compute the        Jti1981 
                       otherwise nearly indeterminate orbit; thus the orbit should not be              
                       used to compute the mass. The RV difference from which the ascending            
                       node is inferred is quite small. Various small variations, formerly             
                       suspected in the period range of about 5-10 years, are absent in the            
                       strong photographic coverage of the last decades.                               
                       See Baize & Petit (1989) catalog of doubles with variable component.    Baz1989d
                       Resulting component masses are 0.74 +/- 0.13 and 0.46 +/- 0.07 Msun.    PkO2006b
                       HIP 104214. See Allen et al. (2000) for information on metallicity,     AlC2000 
                       age, galactic orbital parameters, etc.                                          
                       AB: NLTT 50559/50560                                                    Chm2004 
                       BC: Optical pair, based on study of relative motion of the components           
                       using the method of apparent motion parameters.                         Kiy2008 
           HZE   4     Heinze et al. (2010) determine that the J, K, and L components are all          
                       background objects.                                                     Hze2010 
21070+1500 BPM2327     [PM2000] 2454037 + [PM2000] 2453969.                                    Gvr2010 
21071+1558 BPM2328     [PM2000] 2454427 + [PM2000] 2454414.                                    Gvr2010 
21071+1042 J  2576     Not found by Heintz at IDS position.                                    Hei1990b
21071-2500 SEE 439     24 Cap.                                                                         
21072+3657 SEI1407     ALI 438.                                                                        
21072-1355 BU  157     AC: Optical pair, based on study of relative motion of the components           
                       using the method of apparent motion parameters.                         Kiy2008 
21073-0021 BAL 930     J 3209.                                                                         
21073-5702 HDS3009     This is the C component of 21078-5702.                                  Dam2015b
21074-0814 BU  368     Baize (1985) value of omega corrected from 12.0 to 192.0 degrees by     Baz1985b
                       Ruymaekers & Nys (1985).                                                Ruy1995 
                       AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 3.23 +/- 1.27, 3.31, and 2.24 Msun, respectively.  Mlk2012 
21075+3831 SEI1408     ALI 961.                                                                        
21075-3842 WG  266     CPD-39@8869.                                                                    
21076+1442 BPM2329     [PM2000] 2455520 + [PM2000] 2455335.                                    Gvr2010 
21078+3834 BRT2233     ALI 962.                                                                        
21078+3421 FYM 125     The JK pair was initially listed incorrectly as a new JN pair.          FyM2014b
21078+1345 BPM2330     [PM2000] 2456137 + [PM2000] 2455874.                                    Gvr2010 
21078-5702 HJ 5243     B is CPD-57@9794.                                                               
                       The C component is 21073-5702HDS3009.                                   Dam2015b
21079+3324 TRN  31     The image rotator was in an unknown state, so two possible theta                
                       values are listed for the 2001.7367 observation - one for zenith up             
                       and one for north up. However, the 2MASS measure effectively rules              
                       out one option.                                                         Trn2008 
           HD 201345   Aslanov et al. (1984 SvAL 10, 278) discuss the radial velocities and            
                       the possibility of a low-mass companion.                                Msn1998a
21079+1229 BPM2331     [PM2000] 2456493 + [PM2000] 2456492.                                    Gvr2010 
21080-0104 J  1402     BAL 618.                                                                        
21082+3628 SEI1410     Primary is V2483 Cyg, eclipsing binary of Beta Lyr -type, period                
                       112.4 d.                                                                Zas2012 
21083+2437 SLE 531     Ten arcminute error in declination of primary.                          Sle1986a
21083+3816 SEI1411     ALI 679.                                                                        
21083+1757 BPM2332     [PM2000] 2457297 + [PM2000] 2457104.                                    Gvr2010 
21085+3614 SEI1412     ALI 216.                                                                        
21086+3012 STF2762     A is probably an Alpha CVn-type variable, V389 Cyg. There also may be           
                       a long-period spectroscopic binary in the system.                               
                       AB: H 2  97.                                                            MEv2010 
21086-2112 HJ 3009     chi Cap = 25 Cap                                                                
                       HJ 1617.                                                                        
           VIG  20     The E and F components appear to be co-moving with the primary; the             
                       masses of E and F are estimated at 0.09-0.13 and 0.09-0.14 Msun,                
                       respectively. Optical/physical nature of the G component is undefined.  Vig2012 
21087+7342 OSO 141     G261-038 . Not a common proper motion pair, based on comparison with            
                       POSS2 red plates.                                                       Oso2004 
21087+1145 BPM2333     [PM2000] 2458372 + [PM2000] 2458147.                                    Gvr2010 
21088+1113 BPM2334     [PM2000] 2458615 + [PM2000] 2458474.                                    Gvr2010 
21089+2417 OSO 142     G187-024. Neither is a common proper motion pair, based on comparison           
                       with POSS2 red plates.                                                  Oso2004 
21090+0410 HJ 5515     Nothing in the vicinity matches Herschel's theta value. However, if             
                       either he meant the separation was 15" or his theta has a 90deg error,          
                       this pair appears to be the most likely match.                                  
21091+3844 S   779     B is BD+38@4363.                                                                
21092-0814 JNN 128     The binary 2MASS J21091375-0814041 is as of yet uncomfirmed with                
                       regards to common proper motion, but the components have similar                
                       colors and brightnesses, and a relatively small separation of ~0.97"            
                       hence the pair is probably physically bound, and counts as such in the          
                       statistical analysis.                                                   Jnn2012 
21094-7310 I   379     Measures uncertain, too close. Duplicity doubtful. Needs speckle.               
                       Hipparcos stochastic double solution.                                           
                       AB: Additional notes may be found in Finsen (1951).                     Fin1951a
                       AB: A is SB and astrometric binary, P=6.65y (Goldin & Makarov 2006).    Gln2006 
                       Resolved at 0.14".                                                      Tok2014d
21096-1622 HJ 1612     J 1783.                                                                         
21097+1434 OL  132     Scardia et al. (2013) note that the ID is uncertain for their 2011              
                       measure.                                                                Sca2013c
21098+4001 GRV 429     AC: Also known as GRV 430AB.                                                    
21098+2915 DU    3     Aka WFC 234. DM number incorrectly listed as BD+28 4015 in BDS.                 
21098-1834 HJ 3010     B is BD-19@6033.                                                                
21098-5155 RST1084     CD-52@9770.                                                                     
21099+1648 BPM2335     [PM2000] 2461379 + [PM2000] 2461405.                                    Gvr2010 
21101+1311 BPM2336     [PM2000] 2461843 + [PM2000] 2461635.                                    Gvr2010 
21101-4851 HJ 5247     B is CD-49@13357.                                                               
21102+2045 RAO  25     Pair has a variable RV (Nordstrom et al. 2004), so the 3".3 companion  Nrd2004  
                       B discovered by Robo-AO makes it a triple system (estimated period of  .        
                       AB is 2000 yr, too long to cause the RV variation). We found the B     .        
                       component to be on the [Fe/H] = -0.5 isochrone, in agreement with      .        
                       [Fe/H] = -0.54 measured for A (Reddy et al. 2003 MNRAS 340, 304).      Rbr2015d 
21103+1008 KNT   5     A: gam Equ = 5 Equ. A is an Alpha CVn-type variable. There apparently           
                       is a long-period spectroscopic binary present.                                  
           BU   71     AC: Optical pair, based on study of relative motion of the components           
                       using the method of apparent motion parameters.                         Kiy2008 
21103-0016 LDS4866     NLTT 50691/50692                                                        Chm2004 
21104-0042 BAL 620     J 2338.                                                                         
21105+4742 BU  159     AE: Leavenworth refers to a 14th magnitude star in 337.0".              Lv_1930 
                       Kuiper's 1934 measure was initially added incorrectly as an additional  Kui1961b
                       component, designated KUI 105AF, although he identified his measure             
                       with the Leavenworth pair.                                                      
21105+2227 STF2769     B is BD+21@4485.                                                                
                       One component is a spectroscopic binary.                                        
           SHY 793     BC: HIP 104536 + HIP 102981.                                                    
           STF2769     H N   8.                                                                MEv2010 
21106+3737 HU 1310     Pair certainly identical to ADS 14717 = ES 253, but measures are                
                       discordant (Espin's rho in 1905.75 and his theta in 1923.75). One star          
                       may be variable.                                                        Baz1948d
21106+1307 BPM2338     [PM2000] 2463302 + [PM2000] 2463345.                                    Gvr2010 
21106+1126 BPM2337     [PM2000] 2463104 + [PM2000] 2463308.                                    Gvr2010 
21109+4658 GIC 166     AB: G212-026/G212-027.                                                          
                       NLTT 50746/50747                                                        Chm2004 
21109+4658 JNN 290     BC and BD: G 212-27. Both of the point sources in the AstraLux field            
                       of view are consistent with static background objects that do not               
                       share a common proper motion with the primary star, hence they are              
                       contaminants rather than physical companions. Their colors (dz' = 4.0           
                       +/- 0.3 mag and di' = 3.3 +/- 0.5 mag for the closer point source and           
                       dz' = 4.8 +/- 0.3 mag and di' = 4.3 +/- 0.1 mag for the farther one)            
                       verify this conclusion.                                                 Jnn2014 
21109+2925 BAG  29     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 1.26 +/- 0.32, 1.20, and 0.47 Msun, respectively.             Mlk2012 
21110+2642 BRT3364     Originally published as BRT 221.                                        Brt1928 
21110+1113 BPM2339     [PM2000] 2464166 + [PM2000] 2464300.                                    Gvr2010 
21110+0933 STF2765     AB: H 1  63.                                                            MEv2010 
21111+3618 HO  283     Aa,Ab: The primary was suspected to be a close pair by Hough in 1884,   Ho_1890 
                       but it it was not confirmed later by Hough, Burnham, or                 Bu_1906 
                       Worley.                                                                 Wor1967a
21112+3855 ES 1991     Not found by Heintz at IDS position.                                    Hei1987a
21112+3332 VKI  48     Ross 825.                                                                       
21112-0100 LDS4867     NLTT 50718/50720                                                        Chm2004 
21114+7140 OSO 143     G262-035. Not a common proper motion pair, based on comparison with             
                       POSS2 red plates.                                                       Oso2004 
21114-5220 HU 1626     Primary is eclipsing binary BR Ind (period 0.89277 day).                Zas2010 
                       Light curve and radial velocity combined solution determined.           Zas2017 
21115+3033 ALD   5     J  3224.                                                                        
                       Olivier's angle of 1915, given in ADS, is 90deg too small.              B__1962d
21115-1132 VOU  30     RST 4076.                                                                       
21117+3818 SMA 136     ALI 683. BRT 2234.                                                              
21117+3621 TOB 213     BC: Originally 21117+3619 TOB 213, but secondary was found to be same           
                       as that of 21117+3621 SEI1439. Systems merged, with quadrant flipped            
                       for TOB pair.                                                                   
21117+1821 LDS1051     LDS5246.                                                                        
                       NLTT 50751/50759                                                        Chm2004 
21117+1350 BPM2340     [PM2000] 2465837 + [PM2000] 2466174.                                    Gvr2010 
21118+5959 MCA  67     Aa,Ab: 1983.4341, 1983.7100, 1984.7118:  These three autocorrelograms           
                       were remeasured; the new results are listed.                            McA1987b
                       Aa,Ab: Malkov et al. (2012) derive dynamical, photometric, and                  
                       spectroscopic masses 02.07 +/- 52.22, 27.33, 25.11 Msun, respectively.  Mlk2012 
21120+2410 STT 430     HIP 104660. See Allen et al. (2000) for information on metallicity,     AlC2000 
                       age, galactic orbital parameters, etc.                                          
21121+4543 ES 9005     Previously known as BU  160. Espin refers to it as a faint              Es_1914 
                       star following BU 160.                                                          
21121+1607 BPM2341     [PM2000] 2466649 + [PM2000] 2466492.                                    Gvr2010 
21122+5854 ARG 107     B is BD+58@2236.                                                                
21122+3828 SMA 137     ALI 964.                                                                        
21123+1105 BPMA251     [PM2000] 2467284 + [PM2000] 2466736.                                    Gvr2010 
21123-0142 BAL 263     LYS  37AB. Designation match was originally missed because BAL 264              
                       measure was incorrectly attributed to BAL 263.                                  
21124+1432 HJ 1619     HJ 1620.                                                                        
21124-1500 H 1  47     H I 47.                                                                         
                       Hopmann orbit rejected from Fourth Orbit Catalog ("P over 4000 years")  Wor1983 
                       Apparent typographical error in Hopmann value for semi-major axis       Hop1974 
                       (5".909); value of 15".909 appears better. Still unable to match his            
                       orbit with data, however, despite various quadrant flips of angles,             
                       et cetera. A least-squares fit for remaining elements using data                
                       available to Hopmann and fixing P, T, and e at his published values             
                       yields a = 10".03, i = 101.0, Omega = 312.0, and omega = 343.4                  
                       This is much better fit by linear solution. Orbit still in 6th Catalog,         
                       but default solution now linear and orbit is rejected. Proper motion            
                       of A and B very different.                                                      
21125+1727 BPMA252     [PM2000] 2467718 + [PM2000] 2467798.                                    Gvr2010 
21126+1706 BPM2342     [PM2000] 2467848 + [PM2000] 2467725.                                    Gvr2010 
21127+3807 GUR  12     Incorrectly identified as ES 257 by Guerrero et al.(2014)               Gur2014 
21127-0045 J  1403     BAL 622. RST 5159.                                                              
21128+3907 SEI1447     ALI 965.                                                                        
21128+3014 BAS   7     Aa,Ab: This is likely the 17.8-yr spectroscopic binary of Griffin &             
                       & Keenan                                                                Grf1992b
21129+3014 BUP 227     zet Cyg = 64 Cyg. A is a spectroscopic binary. The Bright Star                  
                       Catalogue lists the spectral type as G8III-IIIaBa0.6.                           
21131+1028 BU 1501     J 177.                                                                          
21134+2813 BRT3365     Originally published as BRT 223.                                        Brt1928 
21135+1559 HU  767     1979.7700: This measure is an average of a power spectrum and an                
                       autocorrelogram measure, listed separately by McAlister & Hendry.       McA1982d
                       1980.7257  This measure was incorrectly attributed to ADS 13944 by              
                       McAlister et al. (1983).                                                McA1983 
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 3.96 +/- 0.66, 3.40, and 1.82 Msun, respectively.             Mlk2012 
21135+0713 BU  270     Star C (mag. about 12, 32") may be physical. Star D (BD+06 4777, 3')            
                       probably is not physical.                                                       
21135-0905 BRT 515     J  3348.                                                                J__1962a
21136+1315 BPM2343     AB: [PM2000] 2470222 + [PM2000] 2470354.                                Gvr2010 
           BPM2344     BC: [PM2000] 2470354 + [PM2000] 2470555.                                Gvr2010 
21137+6424 H 1  48     H I 48.                                                                 Mlr1950b
                       Only elements P and T have been amended by Starikova (1977) from the    Sta1977a
                       orbit of Baize (1950).                                                  Baz1950b
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 3.85 +/- 0.55, 2.04, and 2.52 Msun, respectively.             Mlk2012 
21137+3602 SEI1455     J 1329.                                                                         
21137+2510 POU5273     Many published measures, previously assigned to POU5269, are            Dam2016d
                       re-assigned here with a quad flip.                                              
21137+1115 BPM2345     [PM2000] 2470413 + [PM2000] 2470438.                                    Gvr2010 
21139+1140 BPM2346     [PM2000] 2471075 + [PM2000] 2471020.                                    Gvr2010 
21140+6606 MLB 221     Also known as WFC 236.                                                          
21140+3755 SEI1457     ALI 685. SMA.                                                                   
21140+1305 BPM2347     [PM2000] 2471285 + [PM2000] 2471380.                                    Gvr2010 
21140+1219 BPM2348     [PM2000] 2471301 + [PM2000] 2471385.                                    Gvr2010 
21141+1741 BPM2349     [PM2000] 2471552 + [PM2000] 2471686.                                    Gvr2010 
21141-5428 LDS 735     TSN  38.                                                                        
21142+1135 BPM2350     [PM2000] 2471654 + [PM2000] 2471705.                                    Gvr2010 
21143+3418 STTA216     B is BD+33@4205.                                                                
                       Pair appears in an appendix list, not part of the discoverer's regular          
                       numbering sequence.                                                             
21143+3332 ES 2316     A 1998.8 measure by Lampens et al. (2007) was erroneously attributed    Lmp2007 
                       to this pair and has been withdrawn by the author.                              
21143+1145 BPM2351     [PM2000] 2471993 + [PM2000] 2471708.                                    Gvr2010 
21144+3803 SEI1461     ALI 686. SMA.                                                                   
21145+1000 STT 535     del Equ = 7 Equ.                                                                
                       Spectral types and masses of components assigned by ten Brummelaar et           
                       al., based on adaptive optics observations.                             TtB2000 
                       This is an example of a system whose earlier long period, low-                  
                       eccentricity orbit has been supplanted by a high-eccentricity orbit             
                       of half P due to correct quadrant determination.                                
                       The motion causes double spectral lines over part of the orbit, but             
                       the components are indistinguishable in the spectrum as well as                 
                       visually. The RV curve gives the elements T, e, and the longitude of            
                       periastron somewhat in variance with those of the visual orbit; cf.             
                       Dworetsky et al. (1971).                                                Dwo1971 
                       Pourbaix gives combined solution for this resolved SB2, yielding        Pbx2000b
                       orbital parallaxes and component masses.                                        
                       Arenou (2000) gives combined solution of astrometric orbits and DSBs.   Are2000 
                       Paper includes masses and distances.                                            
                       Muterspaugh et al. (2008) combine PHASES astrometry with speckle and    Mut2008 
                       radial velocity data to derive an orbit for this nearby pair. The               
                       derived parallax is 54.41 +/- 0.14 mas (distance 18.379 +/- 0.048 pc).          
                       Masses of A and B components are nearly identical, at 1.192 +/- 0.012           
                       and 1.187 +/- 0.012 Msun.                                                       
                       AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 2.43 +/- 0.34, 2.45, and 2.33 Msun, respectively.  Mlk2012 
           STF2777     AB,C: Optical pair, based on study of relative motion of the                    
                       components using the method of apparent motion parameters.              Kiy2008 
                       AB,C: H 4  37.                                                          MEv2010 
21146-2849 LDS4872     NLTT 50827/50824                                                        Chm2004 
21147-0050 A   883     AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 21.20 +/- 18.02, 6.44, 2.19 Msun, respectively.    Mlk2012 
           STF2775     AB,C: Star C (mag. 10.52, 21") is probably physical.                            
                       Egbert observed a wide new pair (1879.656, 59.9deg, 99".40, mags 9.0    Egb1879 
                       and 9.5), but listed only a coarse epoch-1880 RA and no other                   
                       identifier other than his initials. Since his RA matched that of                
                       STF2775, the pair was catalogued as STF2775PQ. There appears to be              
                       nothing in the field of STF2775 which matches this pair, however, so            
                       it has been removed from the WDS.                                               
21148+3803 AGC  13     tau Cyg = 65 Cyg.A is a Delta Scuti-type variable.                              
                       Spectral types and masses of components assigned by ten Brummelaar et           
                       al., based on adaptive optics observations.                             TtB2000 
                       Identification of the ascending node is probable although small                 
                       variations of non-orbital origin superimpose on the RV. A is a Delta            
                       Scuti-type variable. A faint star listed as component F is physical;            
                       linear formula given by Heintz.                                                 
                       See Baize & Petit (1989) catalog of doubles with variable component.    Baz1989d
                       AC and AB,D: Optical pair, based on study of relative motion of the             
                       components using the method of apparent motion parameters.              Kiy2008 
                       AB: The Soderhjelm (1999) orbit predicts a separation of 0.734", but    Sod1999 
                       the magnitude difference (published value 2.7mag) may have been too             
                       great.                                                                  Hrt2009 
                       Calculated mass sum is 2.63 +/- 0.12 Msun. There is some indication of          
                       a substellar companion orbiting one of the two stars, but this is               
                       uncertain. This solution uses only a single Keplerian model.            Mut2010b
21148-1713 RST3279     Position angles discordant, no doubt due to the large magnitude                 
                       difference and closeness of the pair.                                           
21148-2555 HJ 3014     Spectrum: A3/5mA5-F3/5.                                                         
21149+3037 BRT 287     Also known as J  3225.                                                          
21150+1750 BPM2352     [PM2000] 2473568 + [PM2000] 2473840.                                    Gvr2010 
21150-2047 HD 202206   GC 29701. Combined solution, based on reduction of Hipparcos                    
                       intermediate astrometric data together with spectroscopic elements              
                       from the Geneva Extrasolar Planet Search Programs home page.            HaI2001 
                       No comoving objects found within separation/magnitude range listed.             
                       However, Chauvin et al. (2006) note finding at least one faint                  
                       background object.                                                      Cvn2006 
                       HD 202206 is a nearly face-on binary orbitted by a brown dwarf.                 
                       Benedict & Harrison (2017) determine astrometric solutions for AB and           
                       AB,c based on HST Fine Guidance Sensor astrometry and published radial          
                       velocities. The resulting period ratio (P_c/P_B = 4.92 +/- 0.01)                
                       supports past assertions that the system architecture requires a 5:1            
                       mean motion resonance. They derive a parallax 21.96 +/- 0.12mas and             
                       masses 0.089 +0.007/-0.006 Msun for B and 17.9 +2.9/-1.8 Mjup for c.    AST2017 
21154-1021 STF2776     B is BD-10@5631.                                                                
                       BC: H 1  46.                                                            MEv2010 
21156+7836 STF2796     B is BD+77@812.                                                                 
                       H 4 103.                                                                MEv2010 
21157+3235 HJ 1628     GYL  50. Goyal identified his pair as BD+31@4102, but his epoch-1900    Gyl1966 
                       coordinates precess to the location of BD+32@4102. No 16" pair is               
                       found in the vicinity of BD+31@4102, and AC2000 notes no "plate flaws"  WFC1998 
                       mistaken for stars on the Potsdam plates used to generate Goyal's               
                       measure. His value of theta may be reconciled with the position angle           
                       of HJ 1628 by assuming he swapped the dx and dy measures between the            
                       two Potsdam coordinates.                                                        
21158+1745 LDS1052     This star possibly has a wide companion at about 9" as noted in e.g.            
                       the WDS catalog. It is however single in the separation range covered           
                       by the AstraLux data.                                                   Jnn2012 
21158+0515 WRH  35     alp Equ = 8 Equ = Kitalpha                                                      
                       A measure on 1980.4853 was incorrectly attributed to HR 8131 in                 
                       McAlister et al. (1983); it actually belongs to ADS 14893.              McA1983 
                       The equinox-1900 coordinates of this star are incorrectly given as              
                       21158+0430 in the first speckle catalogue.                              McA1984b
                       P = 98.800 d, adopted from Rosvick & Scarfe (1991); T = 2447592.1 for   Scf1991b
                       combined spectroscopic/astrometric orbit by Armstrong et al. (1992).    MkT1992b
                       Quoted errors in T and omega are +3.6/-10.1d and +14/-37deg,                    
                       respectively. Errors to Mark III astrometry are given as "error                 
                       ellipses" ; these values are tabulated below, together with filters             
                       used.  Columns include date (BY), major and minor axes of the ellipse           
                       (mas), ellipse orientation (deg), filter effective wavelength (nm):             
                            1989.4493     1.94     0.081     90.9     800,550,450                      
                            1989.4628     0.45     0.049    104.5     800,550,450                      
                            1989.4712     1.23     0.095     90.8     800,550,450                      
                            1989.4766     3.19     0.16      94.7     800,550,450                      
                            1989.5177     3.84     0.57      80.6     800,550,450                      
                            1989.5313     3.69     2.24     114.8     800,550,450                      
                            1989.6021     2.51     0.48     106.5     800,550,450                      
                            1989.6050     1.39     0.36      88.9     800,550,450                      
                            1989.6159     0.99     0.18      88.6     800,550                          
                            1989.6349     0.45     0.22      78.1     800,550                          
                            1989.6430     1.13     0.22     108.2     800,550,450                      
                            1989.6540     2.86     0.10      99.4     800,550                          
                            1989.7060     2.06     0.24      85.5     800,550,450                      
                            1989.7854     4.10     1.65      74.4     800,550,450                      
                            1989.7934     3.04     0.63      75.4     800,550,450                      
                            1989.7961     1.39     0.38      77.9     800,550,450                      
                            1989.8373     0.94     0.091     69.9     800,550                          
                            1989.8482     0.73     0.085     76.1     800,550,450                      
                            1990.4840     1.35     0.22     103.7     800,550,500                      
                            1990.4896     4.72     0.74      93.2     800,550,500                      
                            1990.5743     0.15     0.042     86.4     800,550,500                      
                            1990.5770     0.33     0.080     88.8     800,550,500                      
                            1990.5824     0.26     0.059     94.9     800,550,500                      
                            1990.6536     0.19     0.041     82.4     800,550,500                      
                            1990.6616     0.41     0.079     86.3     800,550,500                      
                            1990.6644     0.29     0.054     85.8     800,550,500                      
                            1990.6698     0.20     0.050     96.2     800,550,500                      
                            1990.6727     0.66     0.086     81.4     800,550,500                      
                            1990.7054     0.34     0.081     81.4     800,550,500                      
                       Pourbaix gives combined solution for this resolved SB2, yielding        Pbx2000b
                       orbital parallaxes and component masses.                                        
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 4.68 +/- 0.20, 5.08, and 3.52 Msun, respectively.             Mlk2012 
21158-5316 FIN 329     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 05.99 +/- 37.68, 3.70, and 1.88 Msun, respectively.           Mlk2012 
                       Docobo & Andrade (2013) derive a dynamical parallax of 8.36 +/- 0.17            
                       mas and component masses 2.32 +/- 0.18 and 2.09 +/- 0.16 Msun (for              
                       spectral type A2.5V) or 8.74 +/- 0.17 mas, 2.04 +/- 0.15 and 1.82 +/-           
                       0.14 Msun (for A6IV). See paper for extensive notes on this system.     Doc2013d
21160+1639 BPM2353     [PM2000] 2475843 + [PM2000] 2475787.                                    Gvr2010 
21161+2951 LDS1053     NLTT 50902/50901                                                        Chm2004 
                       Luyten measure flipped around the E/W line: pa 282 -> 258.              Luy1969 
21162+1629 BPM2354     [PM2000] 2476243 + [PM2000] 2476288.                                    Gvr2010 
21163+4414 HIP 105017  Ren & Fu (2013) calculated an astrometric orbit, combining Hipparcos    Ren2013 
                       Intermediate Astrometric Data with spectroscopic elements by                    
                       Griffin (2000).                                                         Grf2000b
21163-0913 D    24     IW Aqr = 14 Aqr                                                                 
21165+3959 SEI1484     J 1152.                                                                         
21167-0739 STF2781     H I 90, BDS 10874 probably same star.                                           
                       H 1  90.                                                                MEv2010 
21169+3001 MLB 538     MLB 716 may be same star.                                               Hei1978b
21170+4020 SEI1487     V2486 Cyg, Algol (EA) type eclipsing binary, P = 1.27268 d.             Zas2011 
21172-0414 BU  161     B is BD-04@5403.                                                                
21173+5837 BU 1140     A is a spectroscopic triple system, with a period of 5.4d, which may            
                       constitute an eclipsing system, and a long period of 225d.                      
21174+2053 KUI 106     G 145-31. Estimated age 1000-10000 Myr; masses 0.21 +/- 0.08 and 0.15           
                       +/- 0.05 Msun; a ~93.9 au.                                              Jnn2014 
21175+7658 LDS1948     HJL 291.                                                                HJL1986 
21175+1221 HJ  279     C is probably BD+11@4531.                                                       
21176+2556 SLE 380     Soulie (1985) measure in error, apparently due to typo in right                 
                       ascension of secondary.                                                 Sle1985 
21176+2841 MLB 489     BRT 55 is identical                                                     Hei1983a
21176+1711 BPM2356     [PM2000] 2479523 + [PM2000] 2479772.                                    Gvr2010 
21176+1614 BPM2355     [PM2000] 2479500 + [PM2000] 2479720.                                    Gvr2010 
21177+2449 POU5319     AC appears to be the same pair as POU5320, with a quadrant flip.                
21179+3454 STT 433     AB: ups Cyg = 66 Cyg. Burnham refers to a star twice the distance of C  Bu_1906 
                       in 60@. A Variable?                                                             
                       BC: Hipparcos acceleration double solution.                                     
21180-2203 RSS 558     CD-22@15309                                                                     
21181-2931 LDS 738     A is PMS star and X-ray source.                                         Tok2014d
21182+3035 HO  154     Includes V2150 Cyg, a W UMa type eclipsing binary, P = 0.59186d.        Zas2012 
21182+1807 BPMA253     [PM2000] 2480776 + [PM2000] 2480163.                                    Gvr2010 
21183+4244 HJ 1634     B is BD+42@4052.                                                                
                       STF2782.                                                                        
21184+3943 SEI1497     ALI 1156.                                                                       
21184+3749 SEI1495     ALI 687. SMA.                                                                   
21185+4357 68 Cyg      Reports of small radial velocity variability (Alduseva et al. 1982              
                       SvAL 8, 386; Hanni & Pelt 1988 Tartu Astrof. Obs. Teated 89, 200;               
                       Zeinalov et al. 1987 SvAL 13, 90; Musaev & Snezhko 1988 SvAL 14, 68)            
                       probably reflect the presence of line profile variations (Fullerton     Ful1990 
                       1990).                                                                  Msn1998a
21185+1541 BPMA254     [PM2000] 2481450 + [PM2000] 2481288.                                    Gvr2010 
21185+0236 OSO 144     G093-001. Not a common proper motion pair, based on comparison with             
                       POSS2 red plates.                                                       Oso2004 
21186+6235 BU 1502     alp Cep = 5 Cep = Alderamin. Variable?                                          
21186+1134 BU  163     A is a double-lined spectroscopic binary, period 4.0d.                          
                       1986.395, 1986.565: The separation of this difficult partially                  
                       resolved pair was calculated under the assumption that delta V = 1.2            
                       magnitude, but the large number of measurements makes the result                
                       reliable.  The strange character of the observed motion (Tokovinin,             
                       1986 Astron. Circ. No. 1415) is confirmed.                              Tok1985 
                       Spectral types and masses of components assigned by ten Brummelaar et           
                       al., based on adaptive optics observations.                             TtB2000 
                       Mass-sum in good agreement with the complete speckle/spectroscopic      Fek1997 
                       analysis by Fekel et al. (1997).                                        Sod1999 
                       AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 2.44 +/- 1.33, 2.19, and 1.99 Msun, respectively.  Mlk2012 
21187+1417 J  1785     Heintz believes BRT1351 is identical.                                   Hei1985a
21188+0245 BAL2051     Aka OL  220.                                                                    
21188-0847 BU 1503     AC (137.4" @ 99deg): C is the galaxy NGC 7051.                          Dam2010 
21190+3945 STT 434     AB: H 4  39.                                                            MEv2010 
21190+2614 MET  92     Metchev & Hillenbrand (2009) find 5 optical companions within 12" and   Met2009 
                       a physical brown dwarf companion at 11.9", 109d, dK=9.58. Estimated             
                       mass of B 0.02 Msun.                                                    Tok2014d
21190-6013 R   328     B is CPD-60@7460.                                                               
21191+3954 SEI1502     ALI 1157.                                                                       
21191+1244 BPM2357     [PM2000] 2482869 + [PM2000] 2482944.                                    Gvr2010 
21193+5837 BAG   9     Aa,Ab: This companion could be the blue component of the VV Cep system          
                       M1Ib ep + B2V (Cowley, 1969 PASP, 81, 297).                             Bag1984b
21193+1640 BPM2358     [PM2000] 2483419 + [PM2000] 2483504.                                    Gvr2010 
21194+3814 HO  286     Often seen single. Rapid binary, distances small and quadrants                  
                       uncertain. One component is a Cepheid, V1334 Cyg.                               
           CIA   5     Aa,Ab: Gallenne et al. (2013) resolved the primary into an 8,as pair,           
                       and derived a combined spectroscopic/interferometric orbit. Spectral            
                       type of the companion is earlier than B5.5V.                            CIA2013a
                       Masses are 4.9 and 4.0 Msun. Estimated period = 5.3y,                           
                       a = 6.3au = 0.01".                                                      Evs2013 
21196+3948 SEI1503     ALI 1158.                                                                       
21196+1153 BPM2359     [PM2000] 2483964 + [PM2000] 2484103.                                    Gvr2010 
21197+5303 S   786     STTA217. B is BD+52@2911.                                                       
21198+0026 WAA  50     SLW1237.                                                                        
21198-2621 BU  271     A is a spectroscopic binary.                                                    
21199+5841 HLM  39     STI 2565.                                                                       
21199+3948 SEI1507     ALI 1159.                                                                       
21199-5327 HJ 5258     the Ind                                                                         
           MRN   3     Aa,Ab:  Marion et al. (2014) estimate the companion as A5V. Since               
                       Lagrange et al. (2009) have shown the star to have a constant radial    Lgr2009c
                       velocity, the odds for a face-on orbit are high.  Assuming a circular           
                       orbit, the period would be ~1.3y.                                       Mrn2014 
21200+5436 SKF1978     Originally listed as SKF 250, a discoverer designation already in use,          
                       so DD was changed to next available value.                                      
21200+3854 SEI1505     ALI 968.                                                                        
21200-6018 HJ 5256     B is CPD-60@7465. Spectral types F8? F2?                                        
21203-1048 HU   86     A is an Algol-type binary, RY Aqr.                                              
21205+1415 BPM2360     [PM2000] 2485989 + [PM2000] 2485929.                                    Gvr2010 
21206+1537 AG  416     B is BD+15@4392.                                                                
21208-5302 SHY 340     AC: HIP 105388 + HIP 105404. C component = BS Ind.                              
21209+1140 BPM2361     [PM2000] 2486701 + [PM2000] 2486892.                                    Gvr2010 
21209-0136 RST5161     J 1722.                                                                         
21209-0302 JNN 130     LP 697-26.                                                                      
                       2MASS J21205172-0301545 has a companion with brightness and color that          
                       is consistent with expectation, but no common proper motion test has            
                       yet been done.                                                          Jnn2012 
21210+0217 HEI 408     AB: TDT2913.                                                                    
                       AC: (273@, 54.5") may be BAL 1586. A close pair reported Walker was     Wak1966 
                       not seen by Heintz.                                                     Hei1987a
21212+0001 BAL 931     Baillaud appears to have made an error in reducing 1896 AC data.        Bal1943 
21212-2744 HDS3040     LSC  97.                                                                        
21213+1724 BPM2362     [PM2000] 2487714 + [PM2000] 2487808.                                    Gvr2010 
21214+1020 A   617     Both spectra are visible.                                                       
                       For the visual pair West (1976) computed the elements P, T, e, and      Wst1976 
                       longitude of periastron also from the RV's (orbit 3); tentative                 
                       elements a, i, and the node were added by Heintz in order to have a             
                       complete listing in the Fourth Orbit Catalog. Since the components are          
                       visually indistinguishable, the quadrant of the ascending node (but             
                       not the longitude of periastron) is arbitrary; with the node chosen as          
                       listed, the close pair would be the eastern component when the visual           
                       pair is at maximum separation.                                                  
                       The pair was long assumed to have a 12 yr period.                               
                       1980.4853  This measure was incorrectly identified with HR 8131 =               
                       alp Equ in McAlister et al. (1983).                                     McA1983 
                       The component with the slightly weaker lines is an SB1, P = 2.24 d.             
                       (#1297 in Batten et al., 1989).                                         Bte1989 
                       Hipparcos astrometric solution adopted some elements from the orbit of  HIP1997d
                       West & McAlister (1981).                                                Wst1981 
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 2.60 +/- 0.44, 2.43, and 1.13 Msun, respectively.             Mlk2012 
21214-0310 RUC  14     HV Aqr. Spectral type of resolved companion estimated at K2-3V.         Ruc2007 
21214-1219 HJ  280     B is BD-12@5971.                                                                
21215+1122 BPM2363     [PM2000] 2487987 + [PM2000] 2487954.                                    Gvr2010 
21216-1825 ARA 502     aka J  1405. Jonckheere gives the location as "+40s, -1' de la          Skf2009 
                       BD-19 6082".  If you take a sign error in the RA offset (i.e. 40s west          
                       of the BD star rather than east), you land dead on WDS 21216-1825 =             
                       ARA 502 with which it matches.                                                  
21217+1731 BPM2364     [PM2000] 2488508 + [PM2000] 2488731.                                    Gvr2010 
21218+3230 HLM  40     Also appears to be POP1232CD which is not related to 21208+3227.                
                       WDS position of HLM  40 far off and is corrected here.                          
21218+0202 STF2787     B is BD+01@4465a.                                                               
21220+2727 OSO 145     G187-040. Not a common proper motion pair, based on color and                   
                       comparison with POSS2 red plates.                                       Oso2004 
21220-2224 HJ 5265     CD-22@15347.                                                                    
21221+1948 STFB 11     1 Peg. STTA218. B is a spectroscopic binary, P = 1111d, and is                  
                       BD+19@4690. Spectrum K0V.                                                       
                       AB: H 5  20.                                                            MEv2010 
21222+1725 BPM2365     [PM2000] 2489519 + [PM2000] 2489474.                                    Gvr2010 
21223+5734 POP1233     AC: HJL1107.                                                            HJL1986 
21223+1111 BRT1355     J 2577.                                                                         
21223-1455 BU 1262     H N 139.                                                                        
21224+5218 ES 2708     B is BD+51@3051.                                                                
21225+1207 BPM2366     [PM2000] 2490242 + [PM2000] 2490400.                                    Gvr2010 
21226-5547 HU 1536     A is SB, no orbit. No acceleration in the HIP1, only HIP2.              Tok2014d
21227+1101 BPM2367     [PM2000] 2490630 + [PM2000] 2490551.                                    Gvr2010 
21229+2639 BRT3366     Originally published as BRT 224.                                        Brt1928 
21229+0649 HJ 3023     bet Equ = 10 Equ. A is a spectroscopic binary.                                  
21229+0644 ALD  76     BRT 2191.                                                                       
21231+4831 HDS3045     Primary is V2154 Cyg, an Algol-type eclipsing binary, period 2.63064d.  Zas2011 
21234+1543 BPM2368     [PM2000] 2492166 + [PM2000] 2491909.                                    Gvr2010 
21236+1030 BRT1356     J 1787.                                                                         
21237+0422 STF2791     J  1244.                                                                J__1962a
21238+3721 STFA 55     B is BD+36@4537.                                                                
                       Toyota et al. (2009) monitored the RV of the A component every 1-2              
                       months between 2003 Mar - 2007 Nov, using a high-dispersion echelle             
                       (precision ~10 m/s). The star shows a large RV variation; a Keplerian           
                       fit gives a period of 863.8d and an eccentricity of 0.20, which may be          
                       induced by a companion of mass ~8.1 Mjup, by stellar rotation or by             
                       non-radial pulsation.                                                   Toy2009 
21238-0635 S   788     B is BD-07@5550.                                                                
                       Optical pair, based on study of relative motion of the components               
                       using the method of apparent motion parameters.                         Kiy2008 
21241+2519 BU  447     A is a spectroscopic binary.                                                    
21242+1504 BPM2369     [PM2000] 2493806 + [PM2000] 2493594.                                    Gvr2010 
21242-1253 HJ 5517     18 Aqr.                                                                         
21244+1425 BPM2370     [PM2000] 2494287 + [PM2000] 2494124.                                    Gvr2010 
21244-1248 BU  272     BRT2783.                                                                Brt1947 
21244-4100 BU  766     the 2 Mic                                                                       
21247-6814 GC 29928    Hipparcos astrometric solution assumes circular orbit (e = omega = 0).  HIP1997d
21249+4919 ES 2710     Spectral type B9pSi:Cr:Sr:. Variable, V1934 Cyg.                                
21251+1740 BPM2371     [PM2000] 2495561 + [PM2000] 2495394.                                    Gvr2010 
21251+0923 STF2793     AB,C: According to Le Beau, this pair is physical.                      LBu1990c
21251+0157 BAL1588     Secondary not visible in Aladin; probably plate flaw or typographical           
                       error in AC Catalog.                                                            
21252+1742 BPM2372     [PM2000] 2495861 + [PM2000] 2495959.                                    Gvr2010 
21254+1428 BPM2373     [PM2000] 2496287 + [PM2000] 2496260.                                    Gvr2010 
21254+1121 A   887     AB: Closed in in the last 30 years. Needs speckle.                              
                       AC: Based on inspection of the field, the Aitken measure apparently     A__1932a
                       had a typographical error in theta - 112.4 should be 312.4.                     
21255+0203 A  2289     Little observed in recent years despite considerable orbital motion.            
21257+1140 BPM2374     [PM2000] 2496973 + [PM2000] 2497086.                                    Gvr2010 
21258+3640 S   790     69 Cyg.                                                                         
                       AC: H 5  44.                                                            MEv2010 
21258+3329 GYL  56     Hipparcos stochastic double solution.                                           
21260+4144 BLL  54     B is BD+41@4133.                                                                
21264-2025 HWE  56     AC = HDO 165                                                                    
21265+5245 BU  369     There is a 14th mag star a little farther than the companion measured,          
                       in the direction 336deg.                                                Bu_1894 
21266+1611 BPM2375     [PM2000] 2498708 + [PM2000] 2498833.                                    Gvr2010 
21266-4604 HJ 5267     AD = LDS 742.                                                                   
                       A: Unresolved. Variable RV. The companion HJ 5267 at 5" is listed in            
                       the WDS with one measurement and is not seen here. It should be                 
                       considered spurious.                                                    Tok2013b
                       AB: A is SB, no orbit. AB unresolved  with NICI in Tokovinin et al.     Tok2012a
                       (2012), the companion at 5" is not seen.                                Tok2014d
21267+1341 STF2797     B is a Beta Lyrae-type system. A is the variable KP Peg.                        
21267+0527 OSO 146     G025-029. Neither is a common proper motion pair, based on color or             
                       comparison with POSS2 red plates                                        Oso2004 
21267-2225 SEE 446     zet Cap = 34 Cap. CD-22@15388. A is a spectroscopic binary.                     
21268+3732 COU1821     TDT2972.                                                                        
21270+7339 ZUC  15     Primary is white dwarf WD 2126+734 = GJ 828.5 = G261-43. The companion          
                       appears to also be a white dwarf, of temperature ~5000K.                Zuc1997 
21271+3402 ES 2262     Aka TDS1129.                                                            Dam2016d
21271+2405 POU5372     Aka COU 133.                                                            Dam2013 
21272+1408 BPM2376     [PM2000] 2499912 + [PM2000] 2499781.                                    Gvr2010 
21274-0701 HDS3053     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 2.27 +/- 1.37, 2.18, and 2.01 Msun, respectively.             Mlk2012 
21278+3715 SEI1518     ALI 442.                                                                        
21281-4427 CPO 622     CPD-44@10026.                                                                   
21282+1440 BPM2377     [PM2000] 2501916 + [PM2000] 2502158.                                    Gvr2010 
21282-1906 HJ 3029     Primary is eclipsing binary of W UMa -type, period 0.4733 d.            Zas2012 
21282-2144 EGN  26     Single epoch; bound/unbound nature of pair unknown.                     Egn2007 
21282-5510 R   331     CPD-55@9593.                                                                    
21285+3636 ES 2127     ALI 443.                                                                        
21285-0210 BRT 516     BAL 265.                                                                        
21285-1751 LDS 744     NLTT 51319/51320                                                        Chm2004 
21287+7034 LAB   6     Aa,Ab: bet Cep = 8 Cep = Alfirk. The third component was discovered             
                       recently by speckle interferometry.                                             
                       1971.48: Estimated delta m ~ 3 - 4.  Attempts by Couteau (1973 private          
                       communication) to observe the companion visually were unsuccessful,             
                       supporting this large magnitude difference. Some anisotropic features           
                       in the Fourier transform may indicate other companions or                       
                       circumstellar matter.                                                   Lab1974 
                       1975.545, 1975.956: This is the primary of the system bet Cep and is            
                       believed to be a binary of period ~50 yr. There is also evidence of             
                       radial velocity variations. Labeyrie et al (1974) noted anisotropic     Lab1974 
                       features in the power spectrum which might indicate other companions,           
                       but such features were not observed in the power spectrum derived from          
                       these observations.                                                     BLM1978 
                       Aa,Ab: Malkov et al. (2012) derive dynamical, photometric, and                  
                       spectroscopic masses 9.98 +/- 3.28, 12.04, 12.02 Msun, respectively.    Mlk2012 
           STF2806     AB: H 3   6.                                                            MEv2010 
                       AB: Additional notes may be found in Dembowski (1883).                  D__1883 
21287+1627 BPM2378     [PM2000] 2502826 + [PM2000] 2502886.                                    Gvr2010 
21288+6537 OSO 147     G264-006. None is a common proper motion pair, based on comparison              
                       with POSS2 red plates.                                                  Oso2004 
21289+1105 STF2799     STF2911.                                                                        
21290+5844 HDS3058     Aa,Ab: Classification is from Garmany & Stencel (1992 A&AS 94, 211).    HIP1997a
                       The Hipparcos results confirm the CHR 211Aa,Ab pair.                    Msn1998a
                       1994.7001: Very weak detection, possibly an artifact.                   Msn1999b
21291+3102 BRT 288     ES 2441 is identical                                                    Hei1983a
21291+1211 BAR  56     G126-002. See Allen et al. (2000) for information on metallicity,       AlC2000 
                       age, galactic orbital parameters, etc.                                          
                       AC: Additional notes may be found in van den Bos (1963).                B__1963a
21293+1611 BPM2379     [PM2000] 2503886 + [PM2000] 2504152.                                    Gvr2010 
21295+3728 SEI1519     ALI 692.                                                                        
21296+1340 BPM2380     [PM2000] 2504557 + [PM2000] 2504574.                                    Gvr2010 
21297-6016 R   332     CD-60@7720.                                                                     
21299+5256 STF2803     B is BD+52@2951.                                                                
21299+2338 BU  685     2 Peg.                                                                          
21299-0220 JNN 131     The close companion to 2MASS J21295166-0220070 has consistent                   
                       brightness and color with the expectation for a physical companion.             
                       Only one epoch of images exists, hence common proper motion has yet to          
                       be confirmed.                                                           Jnn2012 
21301+1629 BPM2381     [PM2000] 2505701 + [PM2000] 2505863.                                    Gvr2010 
21301+1514 J   198     The 1958 Van Biesbroeck measure is inconsistent with other measures.    VBs1960 
21303-7200 HEI 595     TDT3001.                                                                        
21304+1508 BPM2382     [PM2000] 2506419 + [PM2000] 2506318.                                    Gvr2010 
21305+3701 SEI1521     J  1155.                                                                        
21305-0707 LDS6355     Wolf 921                                                                        
21306+4852 OSO 148     G232-018. Neither is a common proper motion pair, based on comparison           
                       with POSS2 red plates.                                                  Oso2004 
21306+1140 BPM2383     [PM2000] 2506817 + [PM2000] 2506871.                                    Gvr2010 
21308+4827 A   770     Espin calls this HJ 1657, BDS 11057.                                    Es_1932B
21308-2204 OL   76     CD-22@15423.                                                                    
21309+1427 BPM2384     [PM2000] 2507331 + [PM2000] 2507309.                                    Gvr2010 
21310-4822 HJ 5273     LDS 746.                                                                        
21312+8652 STF2858     LDS1957.                                                                        
                       HJL 297.                                                                HJL1986 
21313-0947 BLA   9     Wolf 922. Proper motion +1170 -060.                                             
                       Combined solution by Segransan et al. (2000) from astrometry,           Sgr2000 
                       spectroscopy, and parallax. Solution yields mass and orbital parallax           
                       determination.                                                                  
                       Possible tertiary companion mentioned in Henry et al. (1999) is here    Hen1999 
                       retracted.                                                              TSN2015 
21314+1414 BPM2386     [PM2000] 2508247 + [PM2000] 2508486.                                    Gvr2010 
21314+1302 BPM2385     [PM2000] 2508225 + [PM2000] 2508285.                                    Gvr2010 
21314-2217 HJ 3030     CD-22@15433.                                                                    
21315+1744 BPM2387     [PM2000] 2508419 + [PM2000] 2508303.                                    Gvr2010 
21316-0534 H 5  76     H V 76. bet Aqr = 22 Aqr = Sadalsuud                                            
                       Common proper motion pair with 22058-0019 = alp Aqr.                    Skf2013 
21317-1330 SCJ  29     B is BD-14@6050.                                                                
21318-0155 LDS6356     G026-008. See Allen et al. (2000) for information on metallicity,       AlC2000 
                       age, galactic orbital parameters, etc.                                          
                       NLTT 51459/51458                                                        Chm2004 
21318-4701 RST3287     Not in Michigan Pub. Vol. XI.                                                   
21319+7034 H 5  28     H V 28.                                                                         
21321+1740 BPM2388     [PM2000] 2509576 + [PM2000] 2509430.                                    Gvr2010 
21322+3341 ES 2383     Identical with ES 2384                                                  Hei1995 
21322+1731 BPM2389     [PM2000] 2509800 + [PM2000] 2509636.                                    Gvr2010 
21322+1342 SIG   6     2MASS J21321145+1341584.                                                        
                       Derived spectral types L5 +/- 0.5 and L7.5 +/- 0.5, luminosities 6.3            
                       +/- 1.9 and 3.0 +/- 1.0 (units 10-5 Lsun). Distance 28 +/- 4 pc         Sig2007 
21322+0013 KUI 107     LDS 749. Red and white dwarfs. The primary is a double-lined                    
                       spectroscopic binary, P = 3.76d. G026-009.  Known proper motion                 
                       companion (G026-010, V=14.58) at 2.2' and PA=29 deg. According to       AlC2000 
                       Allen et al., there is a brighter companion at 0.7"                     Oso2004 
21322-3357 B  1009     6 PsA.                                                                          
21324+1553 BPM2390     [PM2000] 2510128 + [PM2000] 2510260.                                    Gvr2010 
21324-2058 LDS6354     CPD-21@7952.  Also known as RSS 562.                                            
                       NLTT 51476/51475                                                        Chm2004 
                       SHY 342. Bayesian analysis by Shaya & Olling (2011) indicates very      Shy2011 
                       high (near 100%) probability pair is physical.                                  
21325+4436 POP 136     BC: The BC component of this group is the small planetary nebula        Skf2009 
                       IC 5117 = HD 205211.                                                            
21325-2631 RST1093     Spectral type M?                                                                
21326+1121 J  1788     Not found by Heintz at IDS position.                                    Hei1990b
21327+3948 HO  604     Variable of unknown class.                                                      
21329+4959 CHR 102     A spectroscopic binary.                                                         
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 6.12 +/- 1.01, 5.92, and 2.24 Msun, respectively.             Mlk2012 
21330+2408 OSO 149     G126-008. Neither AB nor AC is a common proper motion pair, based               
                       on color and comparison with POSS2 red plates                           Oso2004 
21330+2043 STF2804     Mt. Wilson spectral types F5s and F8.                                           
21331+7059 MLB 367     Not found by Heintz at IDS position.                                    Hei1987a
21331+3938 MLB 899     As ascertained by Skiff, the MLB 899 pair is actual the "hourglass-     Skf2007 
                       shaped" double planetary nebula first noted by Humason.                 Hum1921 
21332+6410 MLB 223     Aka TDT3027.                                                                    
21334+3058 KU  132     AB: HJL 292.                                                            HJL1986 
21337+1554 BPM2391     [PM2000] 2512487 + [PM2000] 2512392.                                    Gvr2010 
21338+0147 BLZ   1     LDS5247.                                                                        
21339+5045 HDS3070     Includes V2165 Cyg, an Algol type eclipsing binary, P = 1.962385d.      Zas2012 
21339+1625 BPM2392     [PM2000] 2512801 + [PM2000] 2512746.                                    Gvr2010 
21341+0651 REE   1     PG 2131+066 = IR Peg. White dwarf plus early M main-sequence star.              
                       Distance estimated from photometry and seismology as 632 +150/-111 pc.  Ree2000 
21342-0327 BU  165     HDO 166. Included in list of new doubles (discovery date 1868.62) by            
                       Pei1882; no description given.                                                  
21344+6644 STFA 57     B is BD+66@1416.                                                                
21344+5349 GIC 167     G232-020/G232-021.                                                              
21344+1816 BPM2393     [PM2000] 2513723 + [PM2000] 2513818.                                    Gvr2010 
21345+0930 STF3112     HJL 293. STT 528.                                                       HJL1986 
21346+1551 BPM2394     [PM2000] 2514076 + [PM2000] 2514061.                                    Gvr2010 
21348+3304 GYL  61     Goyal's coordinates match this pair, but his original measure does      Gyl1966 
                       not match anything in the field. Perhaps 182deg was erroneously                 
                       written as 82deg before a quadrant flip?                                        
21348+3204 LSL   1     Some component designations corrected or changed Dec 2004:                      
                       Aa pair --> AD                                                                  
                       Ab pair --> BF                                                                  
                       CD pair --> CG                                                                  
                       Also 11" companion noted in BDS added as AE pair.                       Bu_1906 
21349-4948 HIP 106560  Unresolved. Astrometric and SB with high proper motion and low                  
                       metallicity.                                                            Tok2013b
21351+1433 BPM2395     [PM2000] 2514918 + [PM2000] 2514984.                                    Gvr2010 
21352-3033 HJ 5280     Spectral type M?                                                                
21353+4612 TOR  28     Formerly known as PAN  25.                                                      
21353+2812 CHR 103     A spectroscopic binary, P = 12.2d. Hence triple.                                
                       This system, first announced by McAlister and recalled in a later       McA1984b
                       McAlister paper after repeated attempts at confirmation, has been       McA1993 
                       restored. While perhaps still spurious, the subsequent confirmation or          
                       suspected duplicity (by another technique) makes the discovery                  
                       measurement somewhat more probable.                                             
21354+3837 ES 1995     Not found by Heintz.                                                    Hei1995 
21354-5523 HJ 5276     CD-55@8863.                                                                     
21355+2427 HU  371     Possibly triple; Dominion Astrophysical Observatory spectra showed              
                       a double spectrum.                                                              
                       Only elements P and T have been amended by Starikova (1977) from the    Sta1977a
                       orbit of Baize (1961).                                                  Baz1961a
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 4.87 +/- 3.02, 6.02, and 2.00 Msun, respectively.             Mlk2012 
21355-1846 I   380     HU  965.                                                                        
21356+1731 BPM2398     [PM2000] 2515757 + [PM2000] 2515954.                                    Gvr2010 
21356+1448 BPM2396     AB: [PM2000] 2515709 + [PM2000] 2515636.                                Gvr2010 
           BPM2397     BC: [PM2000] 2515636 + [PM2000] 2515401.                                Gvr2010 
21359+2622 HJ 1661     B is BD+25@4575a.                                                               
21359+1723 BPM2399     [PM2000] 2516368 + [PM2000] 2516253.                                    Gvr2010 
21359+0041 HJ 3039     AB: HJL 294.                                                            HJL1986 
21360+5728 STF2813     Also known as HJ 1672.                                                          
21363+2917 BRT  56     MLB 490 is identical                                                    Hei1980a
21365+1511 BPM2400     [PM2000] 2517297 + [PM2000] 2517260.                                    Gvr2010 
21366+3928 VYS  10     AC+39 60670. VYS 836.                                                           
21369+4025 74 Cyg      Hipparcos astrometric solution assumes circular orbit (e = omega = 0).  HIP1997d
21369-0841 JNN 132     Due to the small separation (~0.24") of the companion detected in the           
                       AstraLux images, physical companionship is very likely, although only           
                       one epoch of images exists so far.                                      Jnn2012 
21370-0617 RST4696     J 3302.                                                                         
21370-3553 CBL 184     SHY 798. Bayesian analysis by Shaya & Olling (2011) indicates very      Shy2011 
                       high (near 100%) probability pair is physical.                                  
21371-1928 H 6   6     H VI 6. eps Cap = 39 Cap. A is a Cepheid and shell star. It is also an          
                       occultation double. B is BD-20@6253.                                            
21372+2511 POU5436     Aka POU5432.                                                                    
21373+5900 HJ 1677     Same as BDS 11149.                                                              
                       KR   54.                                                                        
21374-6811 DON1012     Spectrum: G5/8(V)+(F).                                                          
21375-1618 HJ 5284     B is BD-16@5898.                                                                
21376+0643 STT 443     H 2  62.                                                                MEv2010 
21376+0137 JNN 291     2MASS J21374019+0137137. This newly discovered binary candidate is a            
                       probable member of the bet Pic moving group according to the Schlieder          
                       et al. (2012 AJ 144, 109) study. Its relatively small projected                 
                       separation of ∼4.5 au implies that its orbit could be dynamically       .     
                       constrained in a reasonable timeframe, which makes it a potential               
                       benchmark binary in the future. Estimated age 10-20 Myr; masses 0.11            
                       +/- 0.04 and 0.05 +/- 0.02 Msun; a ~5.2 au.                             Jnn2014 
21376-0023 STF2809     H 4  38.                                                                MEv2010 
           FYM9001AC   Designated by author as FYM 184, homever 00345+5513CD and DE also       FyM2014 
                       designated by author as FYM 184. Redesignated.                          FyM2014c
21376-0744 HJ 1662     LDS 750.                                                                        
21376-2026 YSC 119     BQ Cap. Primary is Beta Lyr type eclipsing binary, period 1.47409d.     Zas2017b
21377+0637 STFA 56     3 Peg. STTA219. A is an occultation double. B is BD+05@4829.                    
                       AB: HJL 295.                                                            HJL1986 
                       AB: H 5  98.                                                            MEv2010 
21378-0751 MCA  68     xi Aqr = 23 Aqr. A long-period spectroscopic binary now resolved by             
                       speckle interferometry. Also an occultation pair.                               
                       This object was misidentified as HR 8265                                McA1978c
           xi Aqr      Gontcharov & Kiyaeva (2002) photocentric (astrometric) orbit is based   Gon2002a
                       on a combination of ground-based catalogs with Hipparcos.                       
21379+2743 MLB1093     AB: COU 13.                                                                     
           HDS3080     Aa,Ab: CC 1299                                                                  
                       Marginal detection of 14th mag secondary, but mass-sum too large and            
                       more GB obs needed to define orbit. (HIP solution is slit-error).       Sod1999 
                       McCarthy (1983) says he resolved this pair using IR speckle             Mcy1983 
                       interferometry at 2.2 and 3.4 microns, but does not include any values          
                       for rho or theta.                                                               
21380+4829 ES  102     Includes V2169 Cyg, a Beta Lyr type eclipsing binary, P = 1.23372d.     Zas2012 
21381+4616 TOR  29     Formerly known as PAN  26.                                                      
21382-8435 TDT3070     This may be the lost pair R   334 with an unusually large error by      Dam2013 
                       Russell.                                                                        
21384+5658 LEE   1     AB: Classification is from Garmany & Stencel (1992 A&AS 94, 211).       Msn1998a
21384+2953 MLB 491     BRT 289.                                                                Brt1929b
21385+0546 HJ  941     4 Peg.                                                                          
21387+2530 CHR 104     This system, first announced by McAlister and recalled in a later       McA1984b
                       McAlister paper after repeated attempts at confirmation, has been       McA1993 
                       restored. While perhaps still spurious, the subsequent confirmation or          
                       suspected duplicity (by another technique) makes the discovery                  
                       measurement somewhat more probable.                                             
21388-0121 BAL 624     J 3278.                                                                         
21390+5729 BU 1143     The classification and orbit of the primary are from Burkholder et al.          
           STF2816     (1997 ApJ 490, 328).  Stickland (1995) found that the spectral line     Stc1995 
           GUI  36     variations result from one close binary (with weak secondary lines)             
           FLE   3     and a stationary component, a conclusion later confirmed by Burkholder          
                       et al.  The speckle resolution of the system (CHR 212Aa,Ab) clearly             
                       supports the view that this is an SB2 plus a distant O star companion.          
                       The C and D components were also observed and appeared to be single.    Msn1998a
                       Classifications of the C and D components are from Hoffleit & Warren            
                       (1991).                                                                 Hof1991 
           STF2816     AC: H 3  71.                                                            MEv2010 
21391+4421 HJ 1673     Also known as HJ 1679 and TDT3082.                                      Dam2010 
21391-1221 VBS  34     RST 5555. A difficult pair. For AB,C see note by van den Bos.           B__1960b
21392+4311 GIC 168     G212-052/G212-051.                                                              
21393+6017 OSO 150     G231-052. Not a common proper motion pair, based on comparison with             
                       POSS2 red plates.                                                       Oso2004 
21393+2043 STT 445     One component may be variable.                                                  
21395+4144 STT 447     AC and AE identified with H 3 110a and H 3 110b. BDS 11145.             Bu_1906 
           ABH 148     AG was incorrectly identified as the EG pair.                                   
21395+3009 A   772     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 3.37 +/- 2.56, 3.29, and 1.82 Msun, respectively.             Mlk2012 
21395-0003 BU 1212     24 Aqr.                                                                         
                       One component is SB; the RV range in the combined light is 45 km/s.             
                       Branham (2005) uses this system illustrate a method for calculating     Bnh2005 
                       orbital elements. His elements are not included in the catalog, as              
                       he considers them only an example.                                              
                       Combined spectroscopic/visual solution by Branham (2007). Additional    Bnh2007 
                       elements: V0 = -13.339 +/- 0.010 km/sec, K1 = -6.921 +/- 0.022 km/sec,          
                       K2 = -9.061 +/- 0.020 km/sec, parallax = 0".014 +/- 0".008,                     
                       fractional mass = 0.433 +/- 0.002.                                              
                       AB,C: Optical pair, based on study of relative motion of the                    
                       components using the method of apparent motion parameters.              Kiy2008 
21395-1913 HJ 3043     B is BD-19@6143.                                                                
21396+4712 HJ 1676     Magnitude of A is from Tycho Catalog; magnitude of B is from the Guide          
                       Star Catalog, but Romero previously calibrated GSC magnitude to         FMR1999g
                       standard photometry.                                                            
21396+0215 BUP 229     25 Aqr.                                                                         
21399+2737 HDS3083     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 0.92 +/- 0.21, 0.86, and 0.75 Msun, respectively.             Mlk2012 
21399+0623 OSO 151     G093-027. AB comprise a common proper motion pair, but AC do not.               
                       According to Carney et al., AB is a visual binary, but nothing is       Crn1994 
                       found in either SIMBAD or the archives.                                 Oso2004 
21399-0842 RST4091     J 1407.                                                                         
21400+5407 GIC 169     Ross 200                                                                        
21400+0911 CHR 105     Lacy & Popper (1984) discovered a previously unknown companion to the   Ppp1984 
                       eclipsing binary EE Peg through its effects on radial velocity and              
                       times of primary eclipse.  Their third component, with a period of              
                       1464 days and a mass ratio of roughly 5 - 12, would be expected to              
                       exhibit a separation from the primary of ~0".03. It thus seems likely           
                       that the object listed here is yet another long-period member of this           
                       system.                                                                         
21401+2632 BRT3367     Originally published as BRT 226.                                        Brt1928 
21401-1640 gam Cap     Hipparcos astrometric solution assumes circular orbit (e = omega = 0).  HIP1997d
                       = Nashira                                                                       
21401-1757 LDS6357     NLTT 51781/51782                                                        Chm2004 
21402+4316 AC   20     A: 75 Cyg                                                                       
21402+3703 SEI1531     J 1146.                                                                         
21404+5735 STF2819     HJL 296.                                                                HJL1986 
                       H 3  72.                                                                MEv2010 
21405+1625 CLO   2     2MASSW J2140293+162518                                                          
                       Aa,Ab: Konopacky et al. (2010) derive a distance of 25 +/- 10 pc and a          
                       system mass of 0.10 +/- 0.08 Msun.                                      Kon2010 
           ALP  26     Physical companionship to this ultracool dwarf ruled out based on I-J           
                       color, using I-band photometry taken at WIYN in August 2002.            AlP2007 
21406+5419 ES   35     A is the semiregular variable RU Cyg.                                           
21412-0729 OSO 152     G026-022. Not a common proper motion pair                               Oso2004 
21414+1245 BPM2401     [PM2000] 2525223 + [PM2000] 2525353.                                    Gvr2010 
21415+8555 TDT3110     See note for 21452+8554 A   775.                                                
21415+5035 COU2444     COU2547.                                                                        
21415+3817 SEI1532     Neither component seen on POSS plate; may be flaws on AC Potsdam plate          
21415-7723 BLM   6     Astrometric orbit by Alden (1939) used P, T, e taken from the           Ald1939b
                       spectroscopic orbit by Colacevich (1935). Not reinvestigated since.     Cla1935 
                       nu Oct.                                                                         
21416+4048 S   796     76 Cyg. A is a spectroscopic binary. B is BD+40@4610.                           
                       AB: H 5  43.                                                            MEv2010 
21417+1735 OSO 153     G126-024. Not a common proper motion pair, based on color and                   
                       comparison with POSS2 red plates.                                       Oso2004 
21417+0625 HU  278     Purported FYM 56AD pair removed on request of author.                   FyM2014b
21417-0036 J  1409     BAL 625.                                                                        
21418+1151 BPM2402     [PM2000] 2525829 + [PM2000] 2525828.                                    Gvr2010 
21420+1856 LBU   2     Aa,Ab: A 1999 measure of 21426+1900 HO  165 by Mason et al. was         WSI2000b
                       erroneously listed under this pair.                                             
           STF2818     Lewis measure erroneously listed as 21426+1900L    50AC, companion      L__1899a
                       to HO  165.                                                                     
21420-2316 SEE 454     41 Cap.                                                                         
21421+3602 ALI 220     No star at AC2000 position of companion - possible plate flaw or                
                       reduction error.                                                                
21421+1328 LDS4904     LDS4855.                                                                        
                       NLTT 51877/51874                                                        Chm2004 
21422+3100 OSO 154     G188-020. None is a common proper motion pair, based on comparison              
                       with POSS2 red plates.                                                  Oso2004 
21422+3008 MLB 575     Heintz described MLB's                                                  Hei1985a
                       confused description.                                                   Mlb1929 
21422-1221 J  1410     BRT 2784.                                                                       
21423+0555 HU  280     Distance in measure given by ADS for 1908.2 (6n, Bry) needs correction.         
                       It represents two annual means: 0.18" in 1907 and 0.30" in 1908; the            
                       latter includes values 0.52", 0.19", 0.18", the first of which must be          
                       rejected, the observer having even noted in addition "not separated".           
                       The same kind of error exists for some other objects on the same night          
                       (BU 151 and HU 371, for example).                                       Mlr1954a
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 2.51 +/- 1.89, 3.75, and 1.82 Msun, respectively.             Mlk2012 
21424+4105 KUI 108     77 Cyg.                                                                         
                       One component is an SB1, P = 1.73 d.                                            
                       The system may be physically related to 21426+4103BU 688 according to   Egg1965b
                       Eggen, and thus quintuple.                                                      
21424+1750 HU  373     BU  691.  The two single star detections of Couteau and van den Bos             
                       may be of the incorrectly identified primary, BD+17 4629.                       
21425+1526 BPM2403     [PM2000] 2526981 + [PM2000] 2527063.                                    Gvr2010 
21425-3756 HJ 5288     B is CD-38@14687.                                                               
21426+4103 BU  688     See KUI 108 note (21424+4105).                                                  
                       Only elements P and T have been amended by Starikova (1984) from the    Sta1984 
                       orbit of Baize (1981).                                                  Baz1981a
                       AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 8.73 +/- 5.21, 3.07, and 1.35 Msun, respectively.  Mlk2012 
21426+1900 HO  165     An 1899 measure by Lewis was erroneously listed as the AC components    L__1899a
                       under the designation L    50. It actually was a measure of STF2818.            
                       A 1999 measure by Mason et al. was erroneously listed under the pair    WSI2000b
                       21420+1856LBU   2Aa,Ab, the A component of STF2818.                             
21429+1537 BPM2404     [PM2000] 2527540 + [PM2000] 2527452.                                    Gvr2010 
21430-2025 SEE 456     HU  967.                                                                        
21432+3801 BLL  55     A is the semiregular variable RV Cyg.                                           
21434+3817 S   799     79 Cyg.                                                                         
                       AB: H 6  57.                                                            MEv2010 
21434+1432 BPM2405     [PM2000] 2528288 + [PM2000] 2528171.                                    Gvr2010 
21435+5847 BU  690     mu Cep = Erakis = Herschel's Garnet Star. A is a semiregular variable.          
21435+2721 A   299     The DE and DF pairs were incorrectly listed as AE and AF in the IDS.            
                       See the ADS for 1875 and 1910 rectangular measures of AD and DE.                
           OSO 155     DG: G188-022. Common proper motion pair.                                Oso2004 
                       Previously entered in WDS as 21440+2723, before primary was identified          
                       as the D component of the A 299 multiple.                                       
21437+0030 CHE 315     There was an error in Chevalier's printed declination, but the offset   Che1909 
                       from his plate center gives coordinates of a pair which agrees with             
                       his measures.                                                           Hrt2012b
21439+2751 HO  166     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 3.70 +/- 1.25, 2.79, and 1.17 Msun, respectively.             Mlk2012 
21440+1705 LDS6358     NLTT 51967/51965                                                        Chm2004 
21440-5720 JC   25     AB: B is CPD-57@9941. Spectral type F6/8IV/V.                                   
                       AB: SHY 344. Bayesian analysis by Shaya & Olling (2011) indicates very  Shy2011 
                       high (near 100%) probability pair is physical.                                  
21441+2845 STF2822     mu Cyg. The A component is a double-lined spectroscopic binary.                 
                       AB: H III 15. D is the principal component of ES 521.                           
                       AC and AD: Optical pairs, based on study of relative motion of the              
                       components using the method of apparent motion parameters.              Kiy2008 
                       AB: H 3  15.                                                            MEv2010 
           ES  521     DE: D is SB2                                                            Tok2014d
           FYM  25     DG pair initially listed incorrected as DH.                             FyM2014b
21441+0709 STTA222     B is BD+06@4891.                                                                
21441-2200 DON1017     CD-22@15541.                                                                    
21442+0953 S   798     eps Peg = 8 Peg = Enif. STTA223 = H 6 103.                                      
                       The primary is variable.                                                        
21443+4234 OSO 156     G212-055. Neither is a common proper motion pair, based on comparison           
                       with POSS2 red plates.                                                  Oso2004 
21443-2348 LDS6360     NLTT 51951/51952                                                        Chm2004 
21444+0008 CHE 316     Also known as DUF   3.                                                          
21445+1446 LUH   4     GJ 9751 = HN Peg                                                                
                       Common proper motion for both components was determined through                 
                       comparison of relative location with that obtained by 2MASS. The B              
                       component is determined to be a possible T dwarf (T2.5 +/- 0.5) based           
                       on mid-IR colors and magnitudes. Age is determined as 0.3 +/- 0.2 Gyr           
                       and mass of secondary 0.021 +/- 0.009 Msun.                             Luh2007 
21446+2539 BU  989     AB: kap Peg = 10 Peg.                                                           
           kap Peg     Double lines have been observed in the spectrum of A.                   Tok2006 
                       The SB1 with P = 5.97 d (#1329 in Batten et al., 1989) is believed to   Bte1989 
                       to be the visual component B, and a set of double lines is observed             
                       which is ascribed to star A (Beardsley & King 1976).                    Bey1976 
                       See Baize & Petit (1989) catalog of doubles with variable component.    Baz1989d
                       Combined solution by Muterspaugh et al. (2006), using PHASES            Mut2006 
                       differential astrometry, iodine cell radial velocities, and published           
                       visual and speckle data. Mass of A is 1.549 +/- 0.050 Msun. Center of           
                       light motion of Ba,Bb pair is seen, allowing determination of masses            
                       for both components: 1.662 +/- 0.064 and 0.814 +/- 0.046 Msun.                  
                       Semimajor axis and error in catalog derived from their values of a              
                       (AU) and parallax, plus errors in those quantities. No sign of                  
                       purported spectroscopic companion to A component. Original tabulated            
                       data are listed below, including date (MJD), dRA and dDEC (mas),                
                       errors in dRA and dDEC (microarcsec):                                           
                       52591.15558   139.4192   -68.9527     337.2   144.9                             
                       52809.42172   176.3305   -52.8124     313.0   223.8                             
                       52834.42590   178.7642   -49.5003     142.0   142.0                             
                       52836.47700   178.2380   -48.6352     377.6   146.9                             
                       52862.26351   179.1262   -46.6494     142.0   142.0                             
                       52864.43495   180.0359   -45.8604     142.0   142.0                             
                       52865.25769   180.3088   -45.0103     142.0   142.0                             
                       52868.42699   179.3844   -45.8741     142.0   142.0                             
                       52891.30945   180.2407   -42.5429     142.0   142.0                             
                       52893.35153   180.8695   -42.7435     312.8   142.0                             
                       52894.33761   181.2314   -42.0489     142.0   142.0                             
                       52895.31028   181.5086   -41.4518     142.0   142.0                             
                       52896.29061   180.7701   -41.3602     142.0   142.0                             
                       52897.28730   180.3950   -41.7411     142.0   142.0                             
                       52915.28300   180.4724   -39.4518     142.0   142.0                             
                       52916.29333   179.8880   -39.7969     329.0   142.3                             
                       52918.11818   181.2814   -38.7883     482.5   330.8                             
                       52919.28864   181.3653   -38.3103     142.0   142.0                             
                       52920.12057   180.8864   -38.2854     661.1   422.9                             
                       52929.26987   181.2990   -38.0007     197.9   142.4                             
                       52930.25991   181.2730   -37.3111     287.3   142.6                             
                       52950.22128   179.7824   -34.3888     839.4   174.7                             
                       52952.20159   180.7612   -35.0063     510.9   145.2                             
                       52983.12402   179.3421   -30.6844     354.1   144.9                             
                       53130.50643   168.6227    -9.8442     467.3   362.7                             
                       53145.46573   168.9574    -7.4882    1766.2  1329.6                             
                       53152.47072   166.1418    -4.9533     142.0   142.0                             
                       53168.42321   164.7537    -3.8669     533.3   376.6                             
                       53172.46749   162.4907    -2.9062     142.0   142.0                             
                       53173.44399   162.7425    -3.3484     142.0   142.0                             
                       53181.41157   162.9387    -0.9785     142.0   142.0                             
                       53182.40964   162.5248    -0.6694     142.0   142.0                             
                       53186.41943   161.7325    -0.6729     142.0   142.0                             
                       53187.40125   162.1831    -0.1186     142.0   142.0                             
                       53197.36300   159.6357     0.5078     142.0   142.0                             
                       53198.39162   160.0532     1.0905     142.0   142.0                             
                       53199.40299   160.6171     1.6181     172.7   147.8                             
                       53200.41220   159.4821     1.7555     389.4   251.1                             
                       53207.41109   157.6318     2.4027     142.0   142.0                             
                       53208.36518   157.5593     2.1577     233.8   165.6                             
                       53215.32511   156.9988     3.2377     142.0   142.0                             
                       53221.38836   156.3834     3.9629     142.0   142.0                             
                       53228.29947   155.6012     5.6284     142.0   142.0                             
                       53229.29186   156.0978     6.1869     142.0   142.0                             
                       53233.24062   154.8590     5.5446     664.9   474.4                             
                       53234.26794   154.9441     6.3985     142.0   142.0                             
                       53235.27795   155.2394     7.0247     142.0   142.0                             
                       53236.24000   154.6541     7.2600     142.0   142.0                             
                       53249.22289   151.8710     8.8380     142.0   142.0                             
                       53270.22848   148.9036    11.8975     243.7   158.7                             
                       53285.23449   145.3500    13.9405     142.0   142.0                             
                       53313.10718   142.2377    18.5964     142.0   142.0                             
                       AB: Martin et al. (1998) derive component masses 1.561 +/- 0.197 and            
                       2.602 +/- 0.284 Msun.                                                   Mig1998 
                       Muterspaugh et al. (2008) combine PHASES astrometry with speckle and    Mut2008 
                       radial velocity data to derive orbits for both the AB and Ba,Bb pairs           
                       of this triple. The parallax is determined at 28.93 +/- 0.18 mas                
                       (distance 34.57 +/- 0.21 pc). Masses of the A, Ba, and Bb components            
                       are 1.533 +/- 0.050, 1.646 +/- 0.074, and 0.825 +/- 0.059 Msun.                 
           STF2824     AB,C (separation 14") has estimated 6200y period.                       Tok2006 
                       AB,C: H N  43.                                                          MEv2010 
                       AB,C: Additional notes may be found in Burnham (1894).                  Bu_1894 
21447+3332 GIC 170     G213-012/G213-013.                                                              
21449+6228 TRN  33     AC: The image rotator was in an unknown state, so two possible theta            
                       values are listed for the 2001.7364 observation - one for zenith up             
                       and one for north up.                                                   Trn2008 
21449-3302 I  1051     iot PsA = 9 PsA. A is a spectroscopic binary. Some doubt as to the              
                       reality of the companion.                                                       
21452+8554 A   775     There is uncertainty due to the high declination, but A   775 appears           
                       to be the same pair as 21416+8555 LDS1959. Systems merged. The pair             
                       21415+8555 TDT3110 has similar separation, but a much different                 
                       position angle.                                                                 
21456+2709 MLB1050     J  2357.                                                                        
21458+1545 STTA224     B is BD+15@4492.                                                                
                       Pair appears in an appendix list, not part of the discoverer's regular          
                       numbering sequence.                                                             
21459+1153 A  1223     AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 2.65 +/- 1.92, 2.54, and 1.05 Msun, respectively.  Mlk2012 
21459-8247 R   334     This may be the new pair TDT3070 with an unusually large error by       Dam2013 
                       Russell.                                                                        
21461+2855 BRT  58     J 2598.                                                                         
21465+0635 UC 4556     aka ITF  69.                                                                    
21466-5742 FIN 283     Soderhjelm feels that there is a probable secondary sub-system. Speckle Sod1999 
                       and spectroscopic observations needed.                                          
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 1.42 +/- 0.77, 1.27, and 0.60 Msun, respectively.             Mlk2012 
21467-0010 BNG   2     Burningham et al. (2009) determine that ULAS J214638.83-001038.7 is a   Bng2009 
                       CPM companion to the high proper motion M4 dwarf Wolf 940. Spectral             
                       type of the companion is T8.5 +/- 0.5. Given the distance to Wolf 940           
                       = 12.50 +0.75/-0.67 pc, the 32" angular separation corresponds to a             
                       projected separation of 400 +/- 22 au. Mass of the companion is 20-32           
                       Mjup, Teff 570 +/- 25K, radius 0.094 +/- 0.004 Rsun. Observations               
                       using Keck laser guide star AO indicated no evidence of any close               
                       companion to the T8 companion. JHK photometry of the primary is from            
                       2MASS.                                                                  TMA2003 
21468+4919 MIU   3     pi 2 Cyg = 81 Cyg. Spectroscopic binary, P = 72d.                               
21470-1608 HJ 3056     del Cap = 49 Cap. A is an Algol-type eclipsing binary, and is also an           
                       occultation double.                                                             
21472+5310 GIC 171     G232-035/G232-034.                                                              
21472+2648 HJ  943     Not found by Heintz.                                                    Hei1995 
21475+1352 BPM2406     [PM2000] 2534610 + [PM2000] 2534626.                                    Gvr2010 
21476+1116 BPM2407     [PM2000] 2534858 + [PM2000] 2534908.                                    Gvr2010 
21477+5942 HD 207538   The classification given in Mason et al. (1998) is from Conti et al.    Msn1998a
                       (1977).                                                                 Cti1977 
21477-1813 CHR 223     First detected as an occultation binary by Evans et al.                 Evn1985 
21477-3054 FIN 330     the PsA = 10 PsA                                                                
                       AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 5.52 +/- 1.62, 5.30, and 2.09 Msun, respectively.  Mlk2012 
                       AB: Docobo & Andrade (2013) derive a dynamical parallax of 11.17 +/-            
                       0.41 mas and component masses 2.32 +/- 0.33 and 2.32 +/- 0.33 Msun.             
                       See paper for extensive notes on this system.                           Doc2013d
21477-7759 LDS6362     Spectrum M?                                                                     
21479+3306 OSO 157     G214-001. Based on astrometry and color, AB comprises the only common           
                       proper motion pair in this system                                       Oso2004 
21479+1824 BPM2409     [PM2000] 2535246 + [PM2000] 2535118.                                    Gvr2010 
21479+1136 BPM2408     [PM2000] 2535182 + [PM2000] 2535291.                                    Gvr2010 
21479-7414 HJ 5287     WFC 237.                                                                        
21480-4736 LDS 755     Bresciano (2012) noted a factor of 10 error noted in Luyten's (1941)    Luy1941 
                       published separation.                                                   Bsc2012 
21483+0518 BRT2294     BAL 2982.                                                                       
21483-3742 B   538     All plates overexposed.                                                 Vou1947a
21483-4718 BSO  15     B is CD-47@13929.                                                               
                       Optical pair, based on study of relative motion of the components               
                       using the method of apparent motion parameters.                         Kiy2008 
21484-5446 RST1109     A is the Beta Lyrae-type variable RU Ind.                                       
21485+6137 D    33     Aka MLB 176 and FOX 99. Identity with Milburn pair first noted by Clif          
                       Ashcraft.                                                                       
21491+6648 STF2836     A is a spectroscopic binary, P = 2.73d.                                         
21492+2256 LDS4910     LDS4911.                                                                        
21492+0543 GIC 172     G093-040/G093-041 = GJ 838.1AB.                                                 
21494+3045 STF2829     B is BD+30@4538.                                                                
21494-4759 SKF1175     The photometry implies a red companion. This wide companion cannot              
                       explain the acceleration.                                               Tok2013b
                       A is possibly an astrometric binary (Makarov & Kaplan 2005).            Mkr2005 
21495+5834 STI2588     STI 2588a.                                                                      
21495-3749 LDS5927     LDS6363.                                                                        
21496-0208 BAL 266     J  3349.                                                                Nsn2016 
21499-2509 B   540     Measures uncertain, too close. Needs speckle.                                   
21500-2127 LDS4913     NLTT 52199/52196                                                        Chm2004 
21500-6319 RST9009     Previously known as RST1110a.                                                   
21501+1717 COU  14     13 Peg. A possible Delta Scuti-type variable. According to Tamazian             
                       et al. secondary is a T Tauri-type variable.                            Tam1999 
                       Calculated mass sum is 2.65 +/- 0.21 Msun.  Spectral classification is          
                       a pair of early F giant or subgiant stars, but this mass sum is more            
                       consistent with dwarfs.                                                 Mut2010b
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 2.56 +/- 0.14, 2.19, and 1.51 Msun, respectively.             Mlk2012 
21501-3837 TOK  36     Confirmed as physical pair by 2nd epoch observation and J-K color.              
                       Primary is 4.9d SB. Estimated period of visual pair 900 y.              Tok2006 
21502+7146 A  1225     Aitken could not find the pair described as HJ 3067,                            
                       allegedly occupying this position.                                              
21506+6024 STI1059     One deg error in WDS designation.                                               
21509-4052 CRU   2     AB = LDS 757.                                                                   
21509-8243 HJ 5278     lam Oct = 10 Oph                                                                
21510+2911 A   889     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 2.04 +/- 0.47, 1.76, and 0.85 Msun, respectively.             Mlk2012 
21511+6650 HU  972     Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 7.17 +/- 3.71, 2.43, and 1.19 Msun, respectively.             Mlk2012 
21512+0321 J  1724     BAL 2059.                                                                       
21515+1806 GIC 173     G126-039.                                                                       
21516+6545 STF2843     AB: Absolute quadrant determined by triple-correlation techniques       Pru2002b
21516+1950 HJ  947     AB: H N  74.                                                            MEv2010 
21518+6453 STF2844     Also known as STI1054.                                                          
21519+4221 HO  172     AD: See ADS for rectangular measures.                                           
                       AD: Optical pair, based on study of relative motion of the components           
                       using the method of apparent motion parameters.                         Kiy2008 
21520+5548 STF2840     A is a spectroscopic binary. B is BD+55@2638.                                   
                       Spectrum A1pSi.                                                                 
                       AB: H 4  79.                                                            MEv2010 
21520+3653 TDT3202     AC: Originally 21520+3652 TDT3202, but share common primary with                
                       21520+3653J  3149, so systems merged.                                           
21521+0739 OSO 158     G093-047. Neither is a common proper motion pair, based on color and            
                       comparison with POSS2 red plates                                        Oso2004 
21522+3252 ES 2321     Aka DOO  88.                                                                    
21524+0938 RED  18     2MASS J21522609+0937575. Spectral types L6: and L6:                     Red2006b
21524+0623 SKF1871     Typographical error in initial WDS designation (21524+0829).                    
21526+3841 MLB 991     ALI 981.                                                                        
21527+1650 BPM2410     [PM2000] 2542347 + [PM2000] 2542248.                                    Gvr2010 
21529-7454 HJ 5295     B is CPD-75@1735.                                                               
21530+2939 BRT  59     This is the same as MLB 494.                                                    
21531+6806 STTA226     BD. Pair initially listed as AD in WDS, but no star of appropriate              
                       magnitude at quoted separation and angle from A. GSC2.3 N1G0000360              
                       appears to be reasonable match in rho and theta (measured from B) and           
                       magnitude, however.                                                             
21532+4324 GRV 517     B component is +42 4236.                                                        
21532+3205 ES 2322     Espin (1928) gives a measure of the pair now designated DE, with the    Es_1928 
                       note "Forms distant comes to B.D. +31 4569, which star has at P. 80deg          
                       an 11.5 nearer, with a 14 mag. S.F." The note is perhaps garbled, as            
                       there is no obvious companion in this system at an angle of 80deg. The          
                       value "11.5" was taken as a separation, but is perhaps more likely a            
                       magnitude. If Espin meant to quote a position angle of 50deg rather             
                       than 80deg, the 11.5 and 14. mag stars may refer to the pair now                
                       designated BC.                                                                  
21534-1411 RST4092     Spectrum: Fm Delta Del.                                                         
21535+5417 BU  841     Perhaps HJ 3066.                                                                
21536+3551 OSO 159     G188-029. Neither is a common proper motion pair, based on comparison           
                       with POSS2 red plates.                                                  Oso2004 
21536-1019 FIN 358     Also an occultation double.                                                     
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 15.09 +/- 14.75, 8.38, and 2.57 Msun, respectively.           Mlk2012 
21538+6237 S   800     A is the Beta Lyrae-type system EM Cep, P = 0.81d.                              
                       Spectrum B0.5V+b1Ve. B is BD+61@2217, spectrum B1III/V.                         
21538-2000 BU  168     A,BC: Aka HDO 168.                                                              
           HU  380     BC: A premature orbit has been computed.                                        
21539+2821 GC 30661    Hipparcos astrometric solution assumes circular orbit (e = omega = 0).  HIP1997d
21540-8036 HJ 5289     B is CPD-81@978.                                                                
21541+1346 BPM2411     [PM2000] 2544365 + [PM2000] 2544356.                                    Gvr2010 
21541-0117 FAR  50     GJ 4236 = NLTT 52377. Primary is white dwarf WD 2151-015.               Far2006 
21541-1710 HIP 108095  NICI images contain a hint of faint companion at ~280deg, 0".12, not            
                       accepted as real.                                                       Tok2012a
21542+0459 OSO 160     G018-005. Neither is a common proper motion pair, based on color or             
                       comparison with POSS2 red plates                                        Oso2004 
21543+1943 STF2841     A,BC: H N  14.                                                          MEv2010 
21543-3957 HJ 5299     B is CD-40@14544.                                                               
21544+1427 BPM2412     [PM2000] 2544898 + [PM2000] 2545037.                                    Gvr2010 
21546-0318 STF2838     Optical pair, based on study of relative motion of the components               
                       using the method of apparent motion parameters.                         Kiy2008 
21549+6159 OSO 161     G264-015. None is a common proper motion pair, based on comparison              
                       with POSS2 red plates.                                                  Oso2004 
21550-1158 HJ  616     Also known as STF2839.                                                          
21552-6153 HDO 296     AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 2.69 +/- 0.39, 2.32, and 1.64 Msun, respectively.  Mlk2012 
           SHY 348     AD: HIP 108195 + HIP 107947.                                                    
                       Also known as CAB   7.                                                  Cab2011 
           SHY 348     AE: HIP 108195 + HIP 107345.                                                    
           SHY 347     DE: HIP 107947 + HIP 107345.                                                    
21553+3239 OSO 162     G188-030. Neither is a common proper motion pair, based on comparison           
                       with POSS2 red plates.                                                  Oso2004 
21554+5938 JNN 292     Estimated age 30-300 Myr; masses 0.14 +/- 0.07 and 0.09 +/- 0.05 Msun;          
                       a ~2.7 au.                                                              Jnn2014 
21554+5608 OSO 163     G232-040. Neither is a common proper motion pair.                       Oso2004 
21555+2942 HO  609     Pair is much fainter than given in the ADS; hence the discordant                
                       separations. Three faint stars are in the field, two south following,           
                       one north preceding.                                                    B__1963a
21555+1053 BU   75     AB: Malkov et al. (2012) derive dynamical, photometric, and                     
                       spectroscopic masses 1.87 +/- 0.60, 2.05, and 0.95 Msun, respectively.  Mlk2012 
21556+3849 A  1449     Baize (1982) orbit rejected from Fourth Orbit Catalog                   Baz1982 
                       ("rescinded by author; omitted from publication")                       Wor1983 
21556+3505 SEI1544     Hipparcos suspected non-single.                                                 
21557+1752 BPM2413     [PM2000] 2546920 + [PM2000] 2546869.                                    Gvr2010 
21558+3716 HO  174     Schembor measures a companion he calls C. 1925.57, 109.5@, 89.74".      Sch1927b
                       CD: Also known as ALI 445.                                                      
21559+3141 ES 2360     BRT 290.                                                                Brt1929b
                       The primary is a spectroscopic binary, P = 6.48d.                               
21560-4234 HJ 5303     B is CD-43@14793.                                                               
21563+7321 MLB 427     LDS1963.                                                                        
21563+1604 BPM2414     [PM2000] 2547721 + [PM2000] 2547747.                                    Gvr2010 
21564+3156 HJ 1707     B is a spectroscopic binary, P = 15.95d.                                        
21565-4102 HJ 5305     A is CPD-41@9730, and B is CPD-41@9729.                                         
21567+6338 WRH  36     Eclipsing binary VV Cep. Visual duplicity uncertain.                            
                       Spectrum of the eclipsing pair composite; M21aep+B8Ve.                          
                       Fredrick orbit rejected from Fourth Orbit Catalog                       Frd1960 
                       ("amplitude below noise level")                                         Wor1983 
21567+1607 STT 455     Mt. Wilson spectral classes are F5 and G5.                                      
21567+1335 BPM2415     [PM2000] 2548460 + [PM2000] 2548269.                                    Gvr2010 
21568+3125 BRT 291     Not found by Heintz.                                                    Hei1995 
21575+2856 LEP 104     NI   42.                                                                        
21575+0409 STTA225     B is BD+03@4639.                                                                
21576+1157 STTA227     B is BD+11@4701.                                                                
21577+1629 BPM2416     [PM2000] 2549795 + [PM2000] 2549712.                                    Gvr2010 
21577-5059 LDS 765     LDS5938.                                                                        
21578-1507 HJ 3071     H N 131.                                                                        
21579+6101 MLR  17     Primary is the Cepheid IR Cep.                                          Evs2016a
21579-4327 LDS 766     Spectrum of A is DA. Spectrum of B M?                                           
21579-5500 FIN 307     del Ind.                                                                        
                       Finsen called attention to quasi-periodic residuals in position                 
                       angle which neither of the alternative orbits explains.                         
                       Illustrative solutions with useable astrometric mass-ratios. Short-P            
                       solution marginally better, but indeterminate with strong element-              
                       correlations. Probably giant primary, more speckle-data needed.         Sod1999 
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 5.24 +/- 0.83, 3.26, and 1.58 Msun, respectively.             Mlk2012 
                       Docobo & Andrade (2013) derive a dynamical parallax of 22.71 +/- 0.69           
                       mas and component masses 1.78 +/- 0.21 and 1.33 +/- 0.16 Msun. See              
                       paper for extensive notes on this system.                               Doc2013d
21580+0556 STF2848     H 3  74.                                                                MEv2010 
21581+1541 BPM2417     [PM2000] 2550355 + [PM2000] 2550535.                                    Gvr2010 
21582+8252 STF2873     LDS1965.  B is BD+82@674.                                                       
                       B comp is 1.2d eclipsing SB2 V376 Cep. Estimated period of AB 7300y.    Tok2006 
                       AB: HJL 298.                                                            HJL1986 
                       AB: A is SB1 (CfA: P=8165d = 22.35y), astrometric binary (Gorshamov et  PkO2006b
                       al. 2006, P=23y), and X-ray source. B is SB2E, P=1.152d                 Tok2014d
21582-2315 LDS4928     NLTT 52553/52552                                                        Chm2004 
21584+4423 LYS  11     The pair previously listed as 22003+4423SMA 156 was found to be this            
                       pair as well. It is actually identified as SMA 143 in the original      Sma1931 
                       publication. The null detection of SMA 156 was therefore, at the        ACA2007 
                       wrong location. Solution to the quandry determined by Wayne Osborn.             
21584-1834 SEE 463     Misidentified in BDS as BD-19@6197.                                             
21585+0347 RAO  73     A is SB1, P=7.184y                                                      Tok2014d
                       A single-lined AB with P = 7.18 yr (Nidever et al. 2002) and a large   Nid2002  
                       PM of 0".28/y. The distant component B at 12".3 is confirmed as        .        
                       physical by 2MASS, Robo-AO, and this work. It is located slightly      .        
                       below the MS, just like HIP 104514B. The object is also metal-         .        
                       deficient relative to the Sun, [Fe/H] = (Zielke 1970 A&A 6, 206).      Rbr2015d 
21585-5901 kap 1 Ind   Hipparcos astrometric solution assumes circular orbit (e = omega = 0).  HIP1997d
21586+0601 SHJ 336     B is BD+05@4913.                                                                
21589-0422 LDS4931     NLTT 52596/52593                                                        Chm2004 
21589-1115 HJ 3075     J 1412.                                                                         
21589-3227 LDS4929     Also known as LHS3739/8. Parallax = 50.92 +/- 0.77 mas.                 Rdl2010 
21592+7311 BU 1509     16 Cep.                                                                         
21592+4102 OSO 164     G214-005. None is a common proper motion pair, based on comparison              
                       with POSS2 red plates.                                                  Oso2004 
21592-3556 LDS 768     LDS5940.                                                                        
21594-1012 LEO  51     J 2362.                                                                         
21595+0617 HJ 3079     AG  279.                                                                        
21597+4907 HU  774     Ambiguous case, although only one solution has been tested.                     
                       Malkov et al. (2012) derive dynamical, photometric, and spectroscopic           
                       masses of 9.18 +/- 5.22, 5.27, and 2.24 Msun, respectively.             Mlk2012 
21598+2356 STF2850     A is an irregular variable.                                                     
21599+5928 STI1078     SMA 155.