TCP J19544251+1722281 in Sagitta

Spectrum by Paolo Berardi, Italy:
http://www.spectro-aras.com/forum/viewtopic.php?f=39&t=2094

CCD observations by Tamás Tordai, Budapest, Hungary using a 0.25m reflector on - 9.815 Aug: 10.85V

Clear skies,

Robert

This variable has been reclassified as ZAND:  by VSX administrators based on the recent observations:
"Sudden brightening on HJD 2458336 (August 5, 2018). It rose from V= 12.5 to 10.7 in only 4 days."

Range: 10.7-13.2V
https://www.aavso.org/vsx/index.php?view=detail.top&oid=572102

ARAS spectral database account for this symbiotic variable:

http://www.astrosurf.com/aras/Aras_DataBase/Symbiotics/TCPJ19544251+172…

Hi Alex,
Vt magnitudes are not V magnitudes so obtaining V magnitudes based on them is not correct.
Also, Tycho-2 magnitudes at 11th mag. are not trustable. When there is no AAVSO sequence for an object, you can get V mags for the comparison stars using APASS. It is available through VizieR.

Also, Tycho identifiers don't carry leading zeroes as the GSC identifiers, so, for instance, it is TYC 1620-2589-1 instead of TYC 1620-02589-1. V is 11.13 so its magnitude was randomly rather consistent with Vt but that is also because it is too blue, B-V is 0.03, a color not recommended for such a red variable.
TYC 1620-749-1 has V= 11.67 and B-V= 0.66. There will surely be a sequence for this object soon.

So in this case the magnitudes were more or less okay but do not use Tycho-2 in the future for stars fainter than 10th mag. And if you use it, use the transformed V not Vt.

Cheers,
Sebastian

Working on a comp sequence now. 

Brad Walter, WBY

A sequence has been created for ASASSN-V J195442.95+172212.6 and is available in VSP. I suggest using a 40 min FOV. All of the stars fall in a 30 min FOV centered on the target but two are very near western edge of a 30 min field. I didn not include the two Tycho stars mention in previous posts. TYC 1620-2589-1 is much too blue for use a comparison star and TYC 1620-749-1 has 4 crowding stars at separation between about 7.6" and 10 seconds. One of the crowding stars is only about 3.7 magnitudes fainter and the second brightest is 4.3 magnitudes fainter (comparisons in the G band). The other two stars are fainter but even closer. 

Hope this helps

Brad Walter, WBY

eShel spectra by Olivier GARDE (ARAS):

http://www.spectro-aras.com/forum/viewtopic.php?f=39&t=2094#p11299

Added 3 sequence stars to fill in between 100 and 11.6. However, you will have to use a 60 min field for these additional stars. 

UVEX2 spectrum by Christian Buil:

http://www.spectro-aras.com/forum/viewtopic.php?f=39&t=2094#p11302

Now it's official:

HBHa 1704-05: a bright and newly discovered symbiotic star, currently undergoing an "hot-type" outburst
http://www.astronomerstelegram.org/?read=11937

AAVSO Alert Notice 648 announces and reports on ASASSN-V J195442.95+172212.6 (TCP J19544251+1722281 = Vend47), a new symbiotic variable. Please see the notice for details and observing instructions.

Many thanks, and Good observing,

Elizabeth O. Waagen, AAVSO HQ

I collected some data on Vend47 last night.  Initial data was OK, but my subsequent time series data was messed up by bands of moon-lit haze crossing the field.

However, there was a suggestion of a sudden dip, like that captured by John Brion (BJFB) on 8/16.  I didn't have enough confidence in my spoiled data to submit it, but I plan to return to this target to see if there's something unusual going on here.

Maybe we can get enough people on this target to even get simultaneous observations of a dip -- if they are real.

Clear skies,

Brad Vietje. VBPA

Newbury, VT

www.nkaf.org

The symbiotic variable star Vend47 (alias HBHa 1704-05 or ASASSN-V J195442.95+172212.6) has been observed from
the space, using the ultaviolet and X-ray intsruments of Neil Gehrels Swift Observatory - reported by A. S. Parikh and R. Wijnands (University of Amsetram) in ATEL #11997.