LMC GCVS variables now in VSX

Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 05/03/2021 - 14:32

Mati Morel (MMAT), a long-time RASNZ and AAVSO member from Australia, has been working very hard over these years, correcting identifications of a large number of variable stars, doing detective work through old papers and plates and always sharing his results with the community.

Recently, Mati has been focused on the Magellanic Clouds variables.
He wrote a series of articles for the VSS Newsletter over the last couple of years, one of them in July 2020, that you can find here:

https://www.variablestarssouth.org/vss-newsletter-july-2020/

He revised 4801 Large Magellanic Cloud objects included in the GCVS's Extragalactic Variable Stars Catalogue (Vol. V), adding remarks and improving their positions using Gaia DR2 when cross-identifications were possible (which was the case for a huge fraction of those stars).

This amazing work has now been incorporated to VSX.
We have checked the list to see how many objects already had VSX entries and how many were "new" (for us).
Many surveys -mostly ASAS and ASAS-SN- have published variables in these sky regions as their findings when they were already known for decades. A lot of them were Harvard Variables. Now we have corrected the names to reflect the fact that they weren't survey discoveries.

We also corrected some minor inconsistencies and left out objects without secure identifications or those that couldn't be found in Gaia DR2.

Some objects classified as miras or red variables that actually had blue colours or inconsistent positions haven't been imported to VSX.

The final result shows 3474 new additions and 647 revisions of LMC objects.
This information can now be found in VSX.

If you have a VSX account, you can log in and use the special search "Changes since last login" and you will see the list of changes.
If not, just write "LMC V%" in the search box and you will get the list of LMC variables that we have in our database.

This is a first step to include Magellanic Cloud variables in VSX.
Historically, galactic variable stars have been our priority, but with the availability of accurate positions from sources like Gaia, and catalogues of thousands of stars like the ones from OGLE, these variables have gained a lot of attention from the community so importing them will be a welcomed improvement.
Having proper identifications and positions for the brighter and long known MC objects will help cross-identifications with variables in prolific survey catalogues like those from OGLE, MACHO or EROS much easier.

Let's thank Mati for his hard work!
And Patrick for importing the list.

Sebastian