American Association of Variable Star Observers (AAVSO)
Tue, 07/18/2023 - 11:59

Dear AAVSO, explain please difference between VSX and AID. I thouht they are synonyms :(

American Association of Variable Star Observers (AAVSO)
A Brief Explanation


VSX and AID are intimately related but they serve two different function. Here is a brief description of each:

VSX - stands for variable star index. It is a repository we keep of all variable stars that are known and information about them such as magnitude, variability, and spectral type among others. It is not completely comprehensive but we are adding to it all the time from various surveys, user submissions, and the like.

AID - stands for AAVSO internation database. This is our database of photometric observations that users submit. If you have ever used webobs, this is where your observations go. Unlike VSX there is no data on the stars properties, but rather how it varies over time. 

Does this help.

Bert Pablo
Staff Astronomer, AAVSO

American Association of Variable Star Observers (AAVSO)
Survey stars and the AID

I accidentally deleted Bert's reply to this posting, so I am going to repeat what he said and expand a bit.

It doesn't matter if a star is a survey star or not. That is only related to the star discovery and its identifier but not to the star nature, or to the importance of observing it.
Any star can be observed if it is interesting and its amplitude is enough to justify putting your time and effort on it.

VSX includes stars from most known surveys.

And the AID will welcome observations of stars having been discovered by anyone, no matter if it is an AAVSO observer, a spacecraft like Gaia or a ground based survey like ASAS-SN.
The only thing that is needed to submit data to the AID is that the star has an AUID in VSX. If it doesn't have it, you can request one and once it is assigned you will be able to submit data.
If the star is a survey star or not, that is not relevant.

I hope this is much clearer now.


American Association of Variable Star Observers (AAVSO)
GCVS stars in the AID and VSX

Hi Mikhail,
I think you still didn't understand the concept:

"Does AID include all GCVS stars or just part of them?"

The AID includes all stars that have had observations submitted. It doesn't matter if they are GCVS stars or not.
Since not all GCVS stars have been observed by AAVSO observers, there is only a fraction of GCVS stars with data in the AID.
But if you want to go out tonight and observe one of those stars and then submit the data, that star will have observations in the AID from that moment on.

VSX includes all GCVS stars.
Not all GCVS stars have AUIDs so if you want to observe one of those, you will need to request an AUID first.

Best wishes,