Almost 41,000 new miras from OGLE

Affiliation
American Association of Variable Star Observers (AAVSO)
Fri, 02/03/2023 - 06:00

We have added another one of those big surveys lists to VSX.

This time, the OGLE Team published a list of more than 66,000 miras:

https://ui.adsabs.harvard.edu/abs/2022ApJS..260...46I/abstract

Almost 41,000 of them turned out to be new additions to VSX.

But it is not only about new additions. Lists like the OGLE one, allows us to improve the information of a large number of known objects in VSX. And even correct wrong identifications caused by the fact that old photographic surveys had low resolution, resulting in ambiguous identifications (also colour information was lacking).
Some of the modern surveys also suffer from blending issues.
1,500 out of the 25,000 objects that were known, had a VSX entry more than 2" away from the actual position. And 271 cases were more than 10" away (!).
In most cases, a nearby star was identified as the variable instead of the correct object.
The worst case was NSVS 13822086, which was actually 47" away from the current VSX position. This is because the Northern Sky Variability Survey resolution was poor, stars within a ~55" radius were usually blended.
The processing of these catalogues and the corrections they allow, will make the import of the larger catalogues like Gaia DR3 and ATLAS easier, since there will be fewer ambiguous identifications and cross-identifications will be more likely to be correct.

So in this first step we have added 40,953 miras to VSX.

You may find them by checking the "Changes since last login" or "Changes in last week" special searches available at the top of the main search page:

https://www.aavso.org/vsx/index.php?view=search.top

Best wishes,
Sebastian