------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 2857 2012 Sep 22 09.17UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074 INTERNET: GUY@TAHQ.DEMON.CO.UK Backup: gmh@wdcc1.bnsc.rl.ac.uk WORLD WIDE WEB http://www.theastronomer.org ------------------------------------------------------------------- SUPERNOVA 2009ip IN NGC 7259 On CBET 1928 issued on 2009 August 29, the discovery of supernova 2009ip in NGC 7259 was reported by J. Maza et. al. during the course of the CHASE project. The object, of then magnitude 17.9 was recorded on 2009 Aug 26 at: RA 22h 23m 08.26s DEC -28° 56' 52.4" (2000), about 36.2"E and 25.1"N of NGC 7259. However rather than a conventional supernova, later reports discussed a subsequent series of LBV eruptions in the object. On ATEL 4334 A. J. Drake reported the discovery of a new bright outburst from spectroscopically confirmed LBV 2009ip on 2012 July 24 during the normal operation of the CRTS SN Hunt project. By 2012 August 14 the source had brightened to V=16.8. This is the highest state observed in SSS data since it was first observed 2005 (pre-discovery images). The 2012 major outburst suggested that the absolute magnitude of SN 2009ip is currently Mv < -14.5. On 2012 Sept 22 Nathan Smith reported on ATEL 4412 pre-discovery images with HST showed a massive blue progenitor star with a ZAMS mass of about 60 M_sun or more as well as pre-outburst variability consistent with a massive eruptive LBV culminating in an eruption with a peak absolute magnitude of -14.5 mag. There was also an outburst in 2010 July with a peak absolute magnitude of about -14. Nathan also reports they obtained low and moderate-resolution spectra using the Steward Observatory B&C spectrograph on the Bok 90" telescope on Kitt Peak on 2012 Sept 15 and 16, which reveal important changes in the spectrum. In addition to the narrow lines reported previously, the new spectra also show very broad lines typical of a normal Type II supernova. H Balmer lines have strong P Cygni profiles, with a minimum in the absorption at -6000 km/s, and a blue edge to the absorption at -13,000 km/s. Although calibrated photometry was not obtained, the object in the guider camera (red sensitive) appeared brighter than at any previous time compared to nearby field stars. It seems probable that the object discovered as SN 2009ip has suffered multiple LBV eruptions, but has now exploded as a genuine core-collapse supernova of Type IIn. Editor: Further observations are urgently required. SUPERNOVA 2012ei IN NGC 5611 HIROSE) 2012ei Aug 22.45 14 24 05.71 +33 02 56.5 14.7 14.1"E 5.8"N P. Ochner et. al: spectrum Aug 23 type-Ia a few days before maximum SUPERNOVA 2012ek IN PGC 62237 (ZHIJIAN XU ET. Al.) 2012ek Aug 18.81 18 40 28.84 +36 07 17.4 17.9 13.6"W 12.2"S M. Turatto: spectrum Aug 21 type-Ib with close similarities to other supernovae of the same type when one week after maximum. POSSIBLE RE-ENTRY WITNESSED, 2012 SEPTEMBER 21 Richard Miles: Already there are 10 videos posted on YouTube of this event and several visual sighting reports on the seesat-l web group. Currently the phenomenon has not been linked to a possible re-entry of a known artificial satellite. So, we are potentially looking at a natural bolide. However, the nature of the break-up would mean that the body of such an object would have been very weak, viz. either a small rubble-pile or possibly cometary in origin. (Please send TA reports to Tony Markham: editor) Guy M Hurst