TCP J18265456-2719122 = Bright 9th mag. transient in Sgr

A bright 9.2 mag. object has been posted to the CBAT “Transient Object Followup Reports” page:

http://www.cbat.eps.harvard.edu/unconf/followups/J18265456-2719122.html

It is in Sagittarius.
We need accurate astrometry because there is some ambiguity about the possible progenitor if the object turns out to be real.
There is a 20.3 Gmag. blue star 0.6" away which would indicate a too large amplitude for a dwarf nova, and a brighter 18.0 Vmag. star 2" away which would make it a possible UGWZ regarding amplitude.

Observations needed!

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Hi Sebastian

I’ve corrected my astrometry on the TOCP page. From my measurements, it appears as though the transient is within 0.12" of the 20.3 Gmag blue star (Gaia 4051881016197528192). I used the Seestar S50 for some multi-colour photometry and it does appear red (B-V = approx. 1.2), recognising that standard filters have not been used.

Regards
Andrew

@Spectroscopy Spectroscopic confirmation needed ASAP! This target is bright (now 9.0V and likely brightening) so please go for it. A low-resolution spectrum would be sufficient to determine whether or not it is a nova. Here’s the VSX link for coordinates and other information: TCP J18265456-2719122. Thank you! - Elizabeth Waagen, AAVSO HQ

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Unfortunately it’s looking like the transient is now fading. I have not performed photometry yet, but it would appear to around 9.4 V.