------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 2530 2009 Mar 05 15.55UT 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 ------------------------------------------------------------------- S/2008 S 1 C. C. Porco, Cassini Team, reports on IAUC 9023 the discovery of S/2008 S 1, an object orbiting within Saturn's G ring in the region between Saturn X/XI (Janus/Epimetheus) and Saturn I (Mimas), in two images of 2008 Aug. 15. Additional detections, yielding 21 total detections during 2007 June 15-2009 Feb. 20 have also been found. A high-precision orbit shows that the object is being influenced by a 7:6 mean-motion resonance with Mimas; averaged orbital elements for S/2008 S 1: a = 167500 km; e = 0.0002, i = 0.001 deg, revolution period = 0.80812 day. S/2008 S 1 is located within a bright arc in the G ring, so this body likely represents a significant source of the small particles found in this ring. If it has the same disk-integrated reflectivity as Saturn XXXIII (Pallene), preliminary estimates of the object's total brightness suggest a physical radius of about 250 m. SUPERNOVA 2009ab IN UGC 2998 Discovery by LOSS of a possible supernova (CBET 1690): SN 2009 UT R.A. (2000.0) Decl. Mag. Offset 2009ab Feb. 8.24 04 16 36.39 +02 45 51.0 18.6 31.2"E,18.4"N M. V. Persson and R. J. Cumming, Stockholm University, report the following preliminary magnitudes obtained on Feb. 9.75 using the 1-m AlbaNova Telescope at Stockholm: B = 16.2, V = 16.5, R = 17.1. Guy M Hurst, Basingstoke, England reports recording this supernova using the Bradford Robotic Telescope. On 2009 Feb 27.77UT photometry of an unfiltered image gave magnitude 15.6 using A2 star magnitudes converted to V. Guy M Hurst