------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 2637 2010 Apr 19 15.54UT 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 ------------------------------------------------------------------- COMET 29P/SCHWASSMANN-WACHMANN 1 Mark Kidger (Herschel Science Centre, European Space Agency, European Space Astronomy Centre reports on behalf of "Observadores_cometas Group" that a major new outburst of Comet 29P/Schwassmann-Wachmann has occurred two days before the Herschel Space Observatory is due to observe the comet. The outburst was first reported on 2010 Apr. 16, 19:22UT at R=12.8 in a 10" square aperture by Estevé Cortés and the Grup d'Astronomia de Mataró (MPC A06, Mataró, Spain), having been last seen at R=16.18 by José Ramón Vidal (MPC 945, Gijón, Spain) on 2010 Apr. 14, 23:19UT. It was confirmed by Ramón Naves & Montse Campàs (MPC 213, Barcelona, Spain) at R=12.76 on 2010 Apr. 16, 20:20UT; Marius Durán (MPC C12, Sabadell, Spain) at R=12.82; and Faustino García (MPC J38, Asturias, Spain) at R=12.82 on 2010 Apr.16, 20:56UT. On 2010 Apr. 17, 21:01UT Naves & Campàs measured R=12.90. This is the 9th largest outburst observed by the Observadores_cometas Group since they started intensive observation of the comet in 2001. The 2010 image gallery for the comet, showing a long sequence of pre- and post-outburst images can be found at http://www.observadores-cometas.com/cometas/29p/imagenes/29p-2010.htm and a historical light curve since 2001 at http://www.observadores-cometas.com/cometas/29p/image008.gif. 29P image gallery for 2010: http://www.observadores-cometas.com/cometas/29p/imagenes/29p-2010.htm (Astronomer's Telegram 2572) In a further report on Astronomer's Telegram 2574 Mark adds: Further observations of the outburst od 29P/Schwassmann-Wachmann 1 show it is following the normal pattern. The observed brightness in a 10" square aperture peaked on 2010 Apr. 16 and has started to decline, as shown by a large number of observations on 2010 Apr. 17 & 18. Mean magnitudes and MPC Site codes of observers are: 2010 Apr. 16, R=12.80+/-0.03 (MPC A06, 213, C12, J38); Apr. 17, R=12.89+/-0.03 (MPC C12, 213, J47, J24, J38); Apr. 18, R=13.13+/-0.03 (MPC A06, 213 [2 observations], A02 [2 observations]). The magnitude was unchanged in a 20" square aperture between Apr. 17 & 18 and was still brightening slowly in a 30" square aperture on Apr. 18. Evolution of the present outburst of 29P: http://www.observadores-cometas.com/cometas/29p/image022.gif SUPERNOVA 2010Y IN NGC 3392 Discovery by Giancarlo Cortini of a possible supernova (CBET 2168): SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010Y Feb 8.87 10 51 03.95 +65 46 47 15.9 15 "E, 7 "S SUPERNOVA 2010Z IN NGC 2797 Independent discoveries by LOSS and Simone Leonini, Italy of a possible supernova (CBET 2169): 2010 UT R.A. (2000.0) Decl. Mag. Offset Observer Feb. 3.34 09 16 21.30 +17 43 40.6 16.7 5.4"W, 2.4"N KAIT Feb. 8.896 09 16 21.25 +17 43 42.4 15.6 8 "W, 4 "N Leonini SUPERNOVA 2010aa IN NGC 692 Discovery by Berto Monrard of a possible supernova (CBET 2171): SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010aa Feb 9.77 01 48 43.21 -49 39 00.7 16.4 11 "E, 7 "S S. Parker (Oxford, Canterbury, New Zealand) found that 2010aa is clearly visible at red mag 15.7 in a prediscovery CCD image taken using a 35-cm Celestron C14 Schmidt-Cassegrain reflector on 2010 Feb. 4.443 Guy M Hurst