[vsnet-alert 21909] TCP J21013299+3957043: new transient (12.3 mag) in Cygnus

[Patrick Schmeer pasc1312-aavso@yahoo.de via vsnet-alert]

TCP J21013299+3957043

RA 21h01m32.99s, DEC +39°57'04.3" (J2000.0)
2018 Feb. 24.7943 UT, 12.3 mag (CCD, unfiltered)
Discoverer: Tadashi Kojima (Gunma-ken, Japan)

"2018 02 24.794 UT
Discovered by T. Kojima, Gunma-ken, Japan, on three frames with five
second exposure using Canon EOS 6D digital camera + 200-mm f/3.2
lens under the limiting mag = 13.0, who writes nothing is visible at
this location on the previous frame (limit mag = 12.8) taken 2018
Feb. 23.810 and also a frame (limit mag = 13.8) on 2017 May 28 UT.
There is a 2MASS star at the position of 33s.44 and 03".7 and also a
star (mag = 15.5) at 34s.03 and 03".5."

Follow-up reports:
http://tamkin1.eps.harvard.edu/unconf/followups/J21013299+3957043.html

The abovementioned '2MASS star at the position of 33s.44 and 03".7'
is the M-dwarf 2MASS J21013344+3957037 = LSPM J2101+3957 with a proper
motion of pmRA= -151 mas/yr, pmDE= -2 mas/yr.
The IPHAS DR2 source IPHAS J210133.03+395703.8 (r=19.15, i=17.87,
ha=18.20 mag) is only 0.7" away from the transient's reported position.

Spectroscopy and precise astrometry are urgently required.

Clear skies,
Patrick