МИИГАиК

MASTER OT J212444.87+321738.3 - new very bright variable

Цитата:

15 марта Бюро Международных Астрономических телеграмм сообщило о вспышки Новой звезды в созвездии Лебедя. Звезда была открыта в ночь с 13 на 14 марта в российской обсерватории 'Мастер-Амур' с помощью 0,4 м рефлектора. Ее звездная величина в момент открытия составляла 10,7 зв.вел. Координаты звезды : 21h 24m 44.87s +32d 17m 38.3s

MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 21h
24m 44.87s +32d 17m 38.3s on 2013-03-13.84134 UT. The OT unfiltered magnitude
is 10.7m (limit 16.9m).
The OT is seen in 6 images. There is no minor planet at this place.
We have reference image with OT at 13.5m on 2012-10-21.52326 UT (magnitude
limit 18.5m).
The object is close to saturation on Mar. 13 images, so the real magnitude
may be yet brighter.

There is nothing at this position in GCVS and AAVSO VSX. No variability
was detected by NSVS (ROTSE-I) project. The object is identical to USNO-B1.0
1222-0647260 (21 24 45.007 +32 17 38.09 B1=18.78 R1=14.96 B2=20.88 R2=16.32
I=13.14), 2MASS 21244500+3217377 (J=7.82+/-0.03 H=5.97+/-0.02 K=4.82+/-0.02)
and WISE J212444.98+321737.73.440 (W1=3.44+/-0.13 W2=2.21+/-0.10 W3=-0.43+/-0.03
W4=-1.28+/-0.01). This area of sky in Cygnus is not covered by CRTS and
GALEX.

The galactic reddening in this direction is A_R=0.55, A_V=0.68 (from Schlegel
et al., 1998) or A_R=0.45, A_V=0.57 (from Schlafly et al., 2011). Color-combined
(BRIR) finder chart is posted at http://master.sai.msu.ru/static/OT/J212444+321738-BRIR.jpg
(10'x10' FOV).

Based on the large (J-K) color index of 3.0 we suggest that MASTER OT J212444.87+321738.3
is a new large amplitude variable of C or S spectral type.
Follow up observations are required.
The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/212444.87321738.3.png

<center><a href="http://observ.pereplet.ru/MASTER_OT.html">List of optical
transients discovered by MASTER</a></center>

Global MASTER Robotic Net: http://observ.pereplet.ru