Gaia DR3 variables

American Association of Variable Star Observers (AAVSO)
Thu, 06/16/2022 - 14:22

Gaia DR3 is out.
And almost 12 million variable stars come with it.
This will have a lot of implications in the variable star community.

They all have a type assigned.
Among them, several million variable stars have periods too.
To give you a rough idea on how amazing this is: the number of eclipsing binaries in this Gaia release is larger than the total number of objects in VSX (which is 2117852 right now).

As it happens with the ATLAS catalogue (and others), checking VizieR to see if the object is already known -even when it is not in VSX-, is mandatory.
The ATLAS catalogue has a lot of issues that make it difficult to import as is, but that will happen eventually.
We are assessing the quality of the Gaia DR3 variability catalogue but the fact that positions and identifications are excellent, will give this a high priority in our list of updates.

This means that finding a new variable star from now on will become a really difficult task.
We are already receiving several messages from individual researchers or groups that use to submit their findings to VSX, asking about this issue.
The short answer is that credit will have to be given to Gaia Collaboration.

For the objects without period information that may have a wrong classification, co-discovery credit might be obtained. We want to encourage observers to work on more complete and accurate analysis of individual objects. E.g. data mining different surveys, obtaining better (and standard) ranges and periods, etc.

Gaia DR3 also offers epoch photometry for lots of objects (available through VizieR) so Gaia data can now be used to complement other light curves.

It will take time to add all these objects to VSX, and in the meantime, keep in mind that you will have to check VizieR to see if the star you are analyzing has already been discovered as variable.
If it is in the Gaia list, you will have to provide the following reference:

Gaia collaboration; et al., 2022, Gaia Data Release 3 (Gaia DR3) Part 4 Variability

Even when this sounds "cataclysmic" (!) for people wanting to find new variable stars, I am sure there will still be things to be found. Gaia's cadence is not high and some interesting variables may have escaped detection.