When the WDS has a proposed orbital solution, it is added to the 6th Orbital Catalog. All orbits are graded, and only those judged of highest grade for each system are included in the published Sixth Catalog. If two orbits for a given system are judged to be of nearly identical quality, the earlier-published orbit is usually chosen for the catalog (unless the later orbit also includes formal errors to the elements). A few systems are found to have two very different sets of orbital elements which yield comparable grades; in these cases both orbits are included. These “special cases” bring the total number of orbits in the current Sixth Catalog to 2,739.
AAVSO Areas of Interest
The American Association of Variable Star Observers (AAVSO) is an international non-profit organization dedicated to variable star research.There are literally hundreds of thousands of variable stars and professional astronomers do not have the time or resources to...