supernova

Special Notice #318: SN 2012hr, a Type Ia supernova prior to maximum

December 23, 2012: SN 2012hr was discovered by Peter Marples (Loganholme, QLD, Australia, Backyard Observatory Supernova Search (BOSS)) [not by Colin Drescher (Calamvale, QLD, Australia; BOSS) as originally reported in AAVSO Special Notice #318; Drescher reported Marples' discovery to CBAT as announced in CBET 3346] on 2012 December 16.53.  The object was discovered at a red magnitude of 14.8.  Subsequent spectroscopy by Milisavljevic et al. and Morrell et al.

Special Notice #312: Supernova 2012gx in MCG -02-2-72 = PSN J00380175-1351395

November 27, 2012: IAU Central Bureau Electronic Telegram 3314 (Daniel W. E. Green, ed.) announces the discovery by A. J. Drake, S. G. Djorgovski, M. J. Graham, A. Mahabal, and R. Williams (California Institute of Technology); R. H. McNaught (Australian National University); J. L. Prieto (Princeton University); M. Catelan (Pontificia Universidad Catolica de Chile); and S. M. Larson and E.

Special Notice #283: Supernova 2012cg IN NGC 4424 = PSN J12271283+0925132

May 23, 2012: IAU Central Bureau Electronic Telegram 3111 (Daniel W. E. Green, ed.) announces the LOSS discovery (reported by M. Kandrashoff, S. B. Cenko, W. Li, and A. V. Filippenko) of a supernova in NGC 4424 on 2012 May 17.22 at unfiltered magnitude 16.9.

Spectra indicating the object to be a Type Ia supernova discovered about two weeks before maximum were obtained by:

Special Notice #256: Request for fast optical time series of SN 2011fe

September 16, 2011: Dr. Bradley Schaefer (LSU) requests fast time series of SN 2011fe over the next several weeks to attempt the detection of fast optical variations in supernova light.

The following request was prepared by Dr. Schaefer which we forward at his request:

SN 2011fe

Welcome to the AAVSO's special webpage devoted to SN 2011fe!

SN 2011fe is the brightest supernova as seen from Earth in nearly 20 years.  It's a rare event that astronomers around the world are excited about -- it's not only a beautiful spectacle, it may also teach us new things about supernovae and the universe that we live in.  Here you'll find information on what SN 2011fe is, why astronomers around the world are watching it, and most importantly, how you can make your own observations and help create a scientific record of this supernova!

Alert Notice 446: Supernova 2011‭fe ‬in M101‭ (‬NGC 5457‭) = ‬PSN J14030581+5416254

August 26‭, ‬2011

Discovered by‭:  ‬The Type Ia supernova science working group of the‭ ‬ Palomar Transient Factory‭:  ‬Peter Nugent‭, ‬Lawrence Berkeley National‭ ‬Laboratory‭ (‬LBL‭), ‬University of California at Berkeley‭; ‬Mark‭ ‬Sullivan‭, ‬Oxford University‭; ‬David Bersier‭, ‬Liverpool John Moores‭ ‬University‭ (‬LJMU‭); ‬D‭. ‬A‭. ‬Howell‭, ‬Las Cumbres Observatory Global‭ ‬Telescope Network Inc‭., ‬University of California at Santa Barbara‭; ‬Rollin Thomas‭, ‬LBL‭; ‬Phil James‭, ‬LJMU

Special Notice #250: Possible Type-Ia Supernova in M101

August 24, 2011: P. Nugent et al. report in ATel #3581 that a possible Type-Ia supernova has been discovered by the Palomar Transient Factory shortly after eruption in the galaxy M101 and has been designated "PTF11kly".  The object is currently at a magnitude of g=17.2, but may well rise by several magnitudes. The object is well placed within M101 for good photometry, and observations of this potential bright SNIa are strongly encouraged.

The (J2000) coordinates reported for the object are

    RA: 14:03:05.81 , Dec: +54:16:25.4