Shattering Shapley’s Universe
Exactly a century ago, on the night of October 5/6, 1923, Edwin Hubble’s photographic observations of a Cepheid variable settled the vexing question of the day: Our Milky Way is not the entire universe.
M31
Alert Notice 615: ASASSN-18ca = PNV J00423439+4044255 - Probable Nova in M31
February 12, 2018
Event: Probable Nova in M31: ASASSN-18ca = PNV J00423439+4044255
Discovered independently by:
- Koichi Itagaki (Yamagata, Japan; reported via CBAT TOCP)
- All Sky Automated Survey for SuperNovae (ASAS-SN) (reported by J. Brimacombe et al. in ATel #11275)
AAVSO Special Notice #260: Retraction of Special Notice #259
October 19, 2011: Further to AAVSO Special Notice #259, D. Fox notes in ATel #3692 that the bright transient in the M31 region reported by Ovcharov et al (ATel #3691) is coincident with the current position of minor planet Palma, currently transiting M31 at a magnitude of V=11.3. The object noted in Special Notice #259 is therefore unlikely to be stellar in nature. Special Notice #259 is therefore retracted.
This AAVSO Special Notice was prepared by M. Templeton.
AAVSO Special Notice #259: Possible bright transient in the region of M31
October 19, 2011: Ovcharov et al. announced the detection of a bright transient in the region of M31 in ATEL #3691 (2011 October 19). They detected an object at R=10.95 on 2011 October 19.818. We are aware of no other confirming observations.
The object is at the following (J2000) coordinates:
RA: 00 44 55.27 Dec: +41 30 58.5
We note that this object is coincident with the blue source LGGS J004455.24+413059.7. Both visual and instrumental follow-up observations are strongly encouraged.
Alert Notice 422: Observing Campaign on Hubble's First Variable in M31: M31_V1
July 16, 2010: An observing campaign is being carried out on M31_V1, the first variable star discovered in M31 by Edwin Hubble. The Hubble Heritage Team, with Dr. Keith Noll, Space Telescope Science Institute (STScI), as Principal Investigator, plans to observe M31_V1 with the Hubble Space Telescope (HST), and needs to know the phase of this Cepheid variable. Although basic parameters are known for this star, no recent photometry exists, so observations are required to generate current phase information.