Since it’s been cloudy here, I’ve been looking at some of the comparison stars in the fields that I image. 000-BCY-344 is listed as a comparison star for AG Dra. It had more than usual scatter in my images so I decided to check whether it was a known or suspected variable. I searched VSX using that designation and it gives me a DSCT star in Cygnus (V2507) quite a distance away. I was under the impression that the UID’s were unique. Am I mistaken?
…Tim (HTY)
Thanks for raising this. I’d be interested in this too. It’s in my sequence for AG Dra.
Greetings,
This is a pretty cool find! We’ll have Sebastian take a look at it next week and report back.
Brian
This opened a can of worms.
We indeed have the AG Dra 119 comparison star with AUID 000-BCY-344 at 16 00 11.22 +66 39 14.2 (J2000.0), not in VSX
And we also have V2507 Cyg with the same AUID 000-BCY-344 and 444 observations in the AID.
This shouldn’t happen, indeed AUIDs are supposed to be UNIQUE.
But there is more to it.
V2507 Cyg has an obsolete entry linked to it, AAVSO 1935+46B, which has another AUID (000-BDC-110) and 601 observations.
That obsolete entry is hidden from view but those observations belong to the same star, and we will have to merge them all so they can be seen in the V2507 Cyg entry.
We will look into the case internally so we can understand what happened and how to avoid similar instances in the future.
V2507 Cyg AUID will be 000-BDC-110 once we correct this, and the 119 comp star will keep 000-BCY-344.
Since you mentioned that the star had more than usual scatter in your images, I went on and checked TESS data for it.
It doesn’t seem to be variable, if it is, it is only at the millimagnitude level (0.002 or 0.003) so we can consider it as constant.
Thanks Tim for calling our attention to this problem.
Cheers,
Sebastian
Thanks for checking the TESS data Sebastian. That’s another tool I can use when I’m getting hinky stats. It’s probably something observational causing my comp jitter.
…Tim