(Hartkopf et al.)
Sample Washington Multiplicity Catalog
William I. Hartkopf & Brian D. Mason
U.S. Naval Observatory, Washington, DC
(last update: 19 June 2003)
The Washington Multiplicity Catalog (WMC) project is an effort to address often
conflicting nomenclature schemes used by astronomers in different fields of double
and multiple star research, by compiling a catalog of all known binary and multiple systems, then
assigning a consistent (insofar as possible) component designation
to each component. This effort was begun shortly before the 2000
IAU General Assembly in Manchester, UK. A sample version of the planned catalog was presented
at IAU Colloquium 191, held in Merida, Mexico in February 2003, and a modified version of this sample
will be presented at the July 2003 GA in Sydney, Australia. Finally, if the nomenclature and
catalog format are agreed upon, a full-sky version of the catalog will be created in time for the
2006 GA in Prague.
A complete library of discussions, IAU resolution, etc. may be found on the WMC home page. A talk was given by one of the authors at the Merida
meeting, outlining the history of the project and the current status of the WMC. A version of
this Merida paper is also available.
The Sample WMC is comprised of doubles and multiples in the 11:00
- 11:30 hr band of right ascension, and combines visual systems from the Washington Double Star
(WDS) database with spectroscopic, interferometric, occultation, astrometric, eclipsing,
interacting, and other systems, both stellar and sub-stellar (e.g., extrasolar planets). A format and reference list describes the columns and lists
the duplicity sources checked so far in the creation of the catalog.
Some modifications were made to the WMC following the Merida meeting - most notably the
conversion of the WMC designation from arcminute to arcsecond precision. It should be noted,
however, that not all planned modifications are complete:
- Coordinate conversion: We discovered that IAU rules for coordinate-based designations
require truncated coordinates, and furthermore that the coordinates themselves listed in a
catalog should have one decimal place of precision more than the designation. We unfortunately
initially used rounded values and kept only arcsecond-precision values for both designation and
coordinates. Both these columns have now been updated.
- Binary types: The WDS database includes a mixture of optical and physical pairs. The "V"
code for visual pairs in the WMC are gradually being replaced with "Vp", "Vo", and "Vc" codes (for physical,
optical, and common-proper-motion pairs, respectively) for systems where this additional bit of
information can be determined (through Keplerian or rectilinear relative motion, for example).
- Links: Links have been included to many of the source catalogs. The WDS summary catalog
will require some changes in its web files to accomodate links to individual objects - this may have to
await other anticipated changes in the catalog.
The main purpose of this sample catalog is to elicit suggestions and comments from
the double star community: additional sources of duplicity information, columns of
information which should be added or seem unnecessary, format suggestions, etc. Your
comments are most welcome (and indeed, are necessary if the full version of this catalog
is to be of use to the community). Please send your comments, suggestions, reports of
errors, etc. to email@example.com. Thank you.
Table of Contents:
Format and References
WMC home page
Return to Double Star Library home page
Return to USNO Astrometry home page