Outburst of VSX J213806.5+261957 (ugwz in Pegasus)

Affiliation
American Association of Variable Star Observers (AAVSO)
Wed, 10/22/2014 - 02:13

I have detected this star at magnitude 9.7 (visual) at 01:25 UT October 22. The previous outburst occurred in May 2010.

The star was fainter than magnitude 13.8 at 03:11 UT October 21.

Carey (CCY)

Affiliation
Vereniging Voor Sterrenkunde, Werkgroep Veranderlijke Sterren (Belgium) (VVS)
Outburst of VSX J213806.5+261957

Very nice catch Carey!!! And already confirmed. This is a big surprise! An UGWZ star with a recurrence-period of only 4,5 years! About the same like in EZ Lyn.

Eddy (MUY)

 

 

 

 

Affiliation
Bundesdeutsche Arbeitsgemeinschaft fur Veranderliche Sterne e.V.(Germany) (BAV)
Outburst of VSX J213806.5+261957

Hi Carey,

I can confirm your observation -  Congratulations!!

Visual 9m,8  - 317/1500mm Newton V = 170x   2014 10. 22. 19:30 UT

Klaus Wenzel (wkl)

Affiliation
British Astronomical Association, Variable Star Section (BAA-VSS)
Nice work Carey.
However as

Nice work Carey.

However as not everyone reads AAVSO forum postings, I wonder why this outburst wasn't announced on CVnet (or vsnet)?  The more people getting data on important oubursts (especially the early stages)  the better surely!  I do not believe that this forum 'alone' is the right place to announce rare outburst detections (others may disagree). Having said that, congratulations on the observation!

Gary [PYG]

Affiliation
American Association of Variable Star Observers (AAVSO)
Congrats, Carey.  I've added

Congrats, Carey.  I've added this to my observing program until it fades back to 15th mag (below my scope's magnitude range).  I hope others will also.  I wonder:  how was it known to be a UGZ and not a classical nova if this is only the second outburst?  Spectroscopy? 

I'd have done a visual estimate last night, but was prepping for today's eclipse :).

Chris

 

 

Affiliation
American Association of Variable Star Observers (AAVSO)
VSX J213806.5+261957

It's looking like a clear night here, I should get some quality imaging done of this star.

Thanks for the alert (baa-vss) Gary.

Douglas.

Affiliation
American Association of Variable Star Observers (AAVSO)
Thanks to everyone for your

Thanks to everyone for your subsequent observations. It was very exciting to see this star in a bright outburst, since it was one I expected I'd have to watch for decades before it did anything again! If I remember correctly an earlier outburst (in 1942) was found in archival photographs.

 

To answer Gary Poyner's question - my internet access is very poor at night and it took me about an hour to submit my observation (via WebObs) and the message above using my telephone. I assumed that by notifying AAVSO immediately I would be "getting the word out" as best I could, but I do welcome other suggestions. Someone advised me to not subscribe to vsnet because of the overwhelming flood of messages, so I don't have access to that group.

 

-Carey (CCY)

 

 

Affiliation
Vereniging Voor Sterrenkunde, Werkgroep Veranderlijke Sterren (Belgium) (VVS)
Time series data reveal superhumps

Hi,

 

I have taken time series data remotely from my observatory ROAD. SUperhumps were visible. Data are normally submitted to AAVSO and VSNET.

I will keep watching the star until end of season.

Regards,

Josch (HMB)

Affiliation
American Association of Variable Star Observers (AAVSO)
VSX J213806.5+261957 companion

Arne,

Since the recent outburst of VSX J213806.5+261957 has renewed interest in this star, I was wondering if precise BVRcIc magnitudes had been determined for the mag 15 companion close to the variable?  I recall you mentioning that high res images of VSX J213806.5+261957 had been obtained with one of the larger professional telescopes back in 2010 and that you were going to do PSF photometry on them.

Thanks,

Bob

Affiliation
American Association of Variable Star Observers (AAVSO)
companion

Hi Bob,

I looked back on the 2010 outburst of this star; interesting to have such a short recurrence!  I looked through various CBET and publications, as well as my own logs, and don't see any high-resolution imaging mentioned.  This was long enough ago that I have forgotten anything that I might have said!

Given that, the most likely source of professional imaging for this period is either from SDSS, the ING, or CFHT.  If someone wants to data-mine, I'll be happy to psf fit any image that you find, though if there is SDSS data, their automated psf fitting is about as good as my manual stuff.

Arne