THE ASTRONOMER Electronic Circular No 733 1993 Apr 22 20.09UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP,England. Telephone/FAX(0256)471074 Int:+44256471074 TELEX: 9312111261 Answerback: TA G TELECOM GOLD: 10074:MIK2885 GMH at UK.AC.RUTHERFORD.STARLINK.ASTROPHYSICS STARLINK: RLSAC::GMH GMH at UK.AC.CAM.ASTRONOMY.STARLINK STARLINK: CAVAD::GMH ------------------------------------------------------------------- THE ASTRONOMER MAGAZINE, APRIL This month's issue was despatched in record time on April 19. It also included a substantial amount of last minute material relating to SN 1993J including two charts with sequences, professional news notes and a detailed light curve. The new deadline system also permitted a number of photographs taken of the supernova in early April to be included. None of these could have been included as they would not have been taken by the old deadline. If anyone who is a non-magazine subscriber requires a copy of this issue please write to the Editor enclosing #1.50. Due to the obvious space constraints imposed by such an exceptional event as SN 1993J, it was unfortunately not possible to include the variable star notes in the April issue but these will be carried forward to May. However in addition a copy of the variable star column was issued by fax and post today via Variable Star Circulars Nos 58-59. If any magazine subscriber who does not receive category 6 circulars would prefer to see the column before the May issue please e-mail the Editor and a copy of the VSCs will be sent. SUPERNOVA 1993J IN NGC 3031 263 visual results and 163 CCD and photovisual results have so far been logged. The supernova apparently reached its first maximum of about magnitude 10.5 visual on JD 2449077 (Mar 30) before fading to around 12.0 on JD 2449083 (Apr 5). It then began a steady rise again reaching around 10.5 on 2449094 (Apr 16). Thereafter a plateau phase seems to have developed although there is just a suggestion of a slight fall in the last few days. The results below show negative observations immediately before the on-set and subsequent positive sightings. If anyone has other photographs/CCD images not yet analysed around the probable on-set date please send results to the Editor as soon as possible. No Obs Logged: 189 263 163 Observer UT Date UT Dec JD Estimate mv rest TypeI Surname 21/01/85 0.000 -2913.50 21.0 r J Cohen 02/10/92 0.000 -102.50 20.0 R Salzer 23/01/93 0.635 11.13 [15.3p Matsumoto 24/02/93 0.687 43.19 [16.0 R Kushida 10/03/93 0.270 56.77 [15.5 W Wren 16/03/93 0.542 63.04 [15.0 R Kushida 16/03/93 0.900 63.40 20.0 R P Prugniel 21/03/93 0.667 68.17 [16.0 Y Okamoto 21/03/93 0.688 68.19 [14.0p Matsushima 23/03/93 0.100 69.60 20.0 R P Prugniel 25/03/93 0.600 72.10 [17 R W van Driel 26/03/93 0.900 73.40 [14.0 F Garcia 26/03/93 0.900 73.40 [14.0 P Pujol 27/03/93 0.036 73.54 [17 O Schneider 27/03/93 0.910 74.41 [16.0 J Merlin 28/03/93 0.300 74.80 13.4 A Neely 28/03/93 0.860 75.36 11.8 F Garcia