------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 2897 2013 Mar 05 19.42UT 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 C/2011 L4 (PANSTARRS) M. Drahus, California Institute of Technology et. al., report on CBET 3429 the detection of HCN in Comet C/2011 L4 on Mar. 1.96UT when at heliocentric distance r = 0.392 AU. A spectrogram taken at the James Clerk Maxwell Telescope shows the J = 4-3 line with area about 1.5 K km/s in the main-beam brightness temperature scale. Assuming an isotropic production of gas at velocity 1.25 km/s and a Boltzmann distribution of energy levels at 100 K, the derived HCN production rate is 5 x 10**26 molecules/s. Selected recent visual magnitude and coma-diameter estimates: 2013 Jan. 7.31UT, 8.0, 2' (W. Souza, Sao Paulo, Brazil, 0.1-m refractor); 16.73, 7.9, 2' (M. Mattiazzo, Victoria, Australia, 25x100 binoculars); 23.81, 7.5, 2'.5 (Andrew Pearce, W. Australia, 0.10-m reflector); Feb. 2.30, 6.4, 5' (Souza, 20x60 binoculars); 12.74, 5.5, -- (David Seargent, NSW, Australia, 6x35 binoculars); 15.73, 5.0, -- (Seargent, naked eye); 19.85, 4.2, 2'.5 (Pearce; altitude 4 deg). SUPERNOVA 2013L IN ESO 216-39 (MONARD) 2013L Jan 22.03 11 45 29.55 -50 35 53.1 15.6 20 "E 24 "S A. Morales Garoffolo: spectrum Jan 28 young type-IIn SUPERNOVA 2013M IN ESO 325-G43 (PARKER) 2013M Jan 20.67 13 59 56.68 -37 51 49.4 17.4R 11 "W Parker has posted an image that can be viewed via website at: http://tinyurl.com/bxep69a S. W. Jha: spectrum Jan 25 type-Ia one week before maximum SUPERNOVA 2013N (THU-NAOC TRANSIENT SURVEY) 2013N Jan 26.79 11 50 04.13 +21 16 46.0 15.9 2 "E 1 "S Jujia Zhang: spectrum Jan 27 type-Ia around maximum SUPERNOVA 2013O (TIANMENG ZHANG ET. AL.) 2013O Jan 21.70 08 52 05.98 +52 36 06.2 18.3 3 "N Jujia Zhang: spectrum Jan 22 type-Ia around maximum SUPERNOVA 2013P IN MCG +05-22-20 (CSS) 2013P Jan 15.43 09 13 37.17 +29 59 58.7 17.0 2.3"W 0.3"N P. Ochner: spectrum Jan 29 type-Ic. SUPERNOVA 2013Q IN NGC 7753 (XINGMING SKY SURVEY) 2013Q Jan 25.58 23 47 07.87 +29 29 11.5 17.5: 34.3"E 11.3"N L. Tomasella: spectrum Jan 30 type-Ia about 10 days before maximum SUPERNOVA 2013R (MASTER) 2013R Jan 06.78 09 31 35.12 +35 23 42.4 16.7 2.2"E 11.6"N L. Tomasella: spectrum Jan 31 type-Ia about 20 days after maximum SUPERNOVA 2013S (THU-NAOC TRANSIENT SURVEY) 2013S Jan 25.60 03 35 30.29 +38 16 59.3 16.1 Tianmeng Zhang: spectrum Feb 4 type-Ia around maximum SUPERNOVA 2013T IN UGC 8250 (CSS) 2013T Jan 22.36 13 10 19.68 +32 28 25.7 17.0 5.8"W 33.8"S L. Tomasella: spectrum Jan 31 type-Ia about 40 days after maximum Guy M Hurst