------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 1457 1999 Oct 16 13.09UT 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 GMH at AST.STAR.RL.AC.UK WORLD WIDE WEB http://www.demon.co.uk/astronomer ------------------------------------------------------------------- SUPERNOVA 1999eh IN NGC 2770 (=Q1999/280) On 1999 October 14 at 04.14UT an e-mail was received from Mark Armstrong reporting a further suspected supernova. Tom Boles obtained a confirmatory image on Oct 14 at 04.59UT but it was necessary to ensure the object was not there previously. This was resolved on the evening of October 14 and after spectral confirmation the Central Bureau issued the following: G. M. Hurst, Basingstoke, England, reports the discovery by Mark Armstrong, Rolvenden, of a supernova (mag about 17.5) on an unfiltered CCD frame taken on Oct. 12.1375 UT with a 0.30-m telescope in the course of the U.K. Nova/Supernova Patrol. In response to an alert, T. Boles, Wellingborough, obtained a confirmatory image on Oct. 14, and Armstrong also secured a further image on Oct. 14.157 showing the new object at about the same brightness. Precise positions measured by Armstrong from his Oct. 12 and 14 images yield R.A. = 9h09m32s.67, Decl. = +33o07'16".9 (equinox 2000.0). Armstrong's measurement of Boles' image yields position end figures 32s.55, 16".3. Research by Hurst indicates that SN 1999eh is absent from the Vickers Deep Space CCD Atlas: North (1993, p. 96; limiting mag about 19) and from both Palomar Sky Surveys (limiting mag about 20). S. Jha, P. Garnavich, P. Challis, and R. Kirshner, Harvard- Smithsonian Center for Astrophysics, report that a spectrum of SN 1999eh, obtained by M. Calkins on Oct. 15.5 UT with the F. L. Whipple Observatory 1.5-m telescope (+ FAST spectrograph), shows it to be a type-Ib supernova. The spectrum exhibits a flat continuum and broad absorption features with He I (rest 587.6, 706.5, and 492.2 nm) being most prominent. There is also evidence of weak [O I] emission, indicating that the supernova is about 2 months past maximum light. IAUC 7282 Editor: This brings to six the number of supernovae found by Mark. Our congratulations once again! TA AGM 1999 The programmes for the above event were posted yesterday so please e-mail if anyone has not received these by early next week. The list of speakers needs amendment. The talk for 12.45 by myself is to be deleted and replaced by: Occultations of stars by asteroids: Hazel McGee (Apologies to Hazel for this omission!-Ed) Guy M Hurst