[vsnet-alert 18897] ASASSN-15ni: bright (12.9 mag) transient in Her (ATel #7850)

[Patrick Schmeer]

ASAS-SN Discovery of a Very Bright Optical Transient
(ATel #7850; Credential Certification: Subo Dong)

During the ongoing All Sky Automated Survey for
SuperNovae (ASAS-SN or "Assassin"), using data
from the quadruple 14-cm "Brutus" telescope in
Haleakala, Hawaii, we discovered a new transient source: 
Object       RA (J2000)   DEC (J2000)     Disc. UT Date     Disc. V mag 
ASASSN-15ni  18:39:58.064  +22:21:17.80    2015-07-28.40     12.9 

ASASSN-15ni was discovered in images obtained on
UT 2015-07-28.40 at V~12.9 mag. We do not detect
(V>17.3) the object in images taken on UT 2015-07-24.42
and before. Images obtained by LCOGT 1.0m A in
Dome A at Siding Spring on UT 2015-07-28.58 confirm
the discovery of the transient. This figure shows the
archival DSS images in red (left) and blue (middle) and
the LCOGT V-band confirmation image (right). The red
circle has a radius of 3" and is centered on the position
of the transient in the LCOGT image. There is no known
source within 4" in any catalogs listed in VizieR Service.
There appears to be a faint source at the position of the
transient in archival DSS blue image. 

The nature of the optical transient is unknown. Follow-up
observations, especially spectroscopic, are encouraged. 
...

Complete text: http://www.astronomerstelegram.org/?read=7850

Clear skies,
Patrick