MASTER-SAAO: very bright optical transient
ATel #7847; V. Vladimirov, V. Lipunov, E. Gorbovskoy (Lomonosov MSU), D. Buckley (SAAO), P. Balanutsa, A. Kuznetsov, N. Tiurina, V. Kornilov, D. Vlasenko, I. Gorbunov, V. Chazov (Lomonosov Moscow State University, Sternberg Astronomical Institute), S. Potter, M. Kotze (South African Astronomical Observatory), R. Rebolo, M. Serra-Ricart , N. Lodieu, G. Israelian (The Instituto de Astrofisica de Canarias), O. Gress, N. M. Budnev, K. Ivanov (Applied Physics Institute, Irkutsk State University), A. Tlatov, D. Dormidontov, V. Senik, A. V. Parhomenko (Kislovodsk Solar Station of the Pulkovo Observatory), V. Krushinski, I. Zalozhnykh (Ural Federal University), Yu. Sergienko, A. Gabovich, V. Yurkov (Blagoveschensk Educational State University)
on 27 Jul 2015; 21:27 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)
Subjects: Optical, Request for Observations, Cataclysmic Variable, Nova, Transient
MASTER OT J111724.72-200029.2 discovery - possible Nova with Amplitude more then 7.3m (no any VIZIER source)
MASTER-SAAO auto-detection system ( Lipunov et al., Advances in Astronomy, MASTER Global Robotic Net, 2010 )
discovered OT source at (RA, Dec) = 11h 17m 24.72s -20d 00m 29.2s on 2015-07-25.74441 UT.
The OT unfiltered magnitude is 14.7m (the limit is 18.8m). There are 3 images with OT on 2015-07-25 (25.74996, 25.75532 UT).
There are 4 images with m=15.3 on 2015-07-27.72022, 27.732. We have reference images without OT on 2015-01-21.90010 UT with 20.2 unfiltered magnitude limit.
There is no minor planet at this place. There is no any source in VIZIER database inside 10". So we can suggest the Nova outburst with amplitude more then 7.3m or possible dwarf nova outburst.
Spectral observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/111724.72-200029.2.png
List of Optical Transients discovered by MASTER
MASTER Global Robotic Net
