------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 1170 1997 Feb 14 18.06UT 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 ------------------------------------------------------------------- OCCULTATIONS ALERT: THREE EVENTS PREDICTED FOR FEBRUARY 18/19 Richard Miles, Asst.Director, Asteroids and Remote Planets reports: Predictions indicate that three interesting and favourable asteroid occultations are potentially visible from the UK and W.Europe next Tuesday night/Wednesday morning (1997 February 18/19). They are: 1) 445 Edna occults a relatively bright star (PPM 68862, V=6.7) at 22:44UT, medium max. duration of 5 sec approx. (N.B. 100 Hekate is forecast to occult PPM 128061 (V=12.8 at 22:59 +/-10 min) as seen from Scandinavia. This event is much less favourable than the 445 Edna event and is not recommended for UK observers) 2) 2761 Eddington occults a relatively faint star (GSC 1904 1183, V=12.2) at 04:18 UT, long max. duration of 14 sec approx. 3) 532 Herculina occults GSC 6266 2247 (V=10.2) at 05:52 UT, medium max. duration of 6 sec. approx. Events involving 532 Herculina are particularly interesting since this object may have a companion satellite, since a secondary occultation has been reported in the past. Observers are encouraged to attempt timings of any or all of these events. The first event involves a particularly bright star at a high altitude and takes place at a convenient time in the evening so should be accessible to a very large number of observers. The shadow track has a good width extending some 150 km. The second event is the least favourable of the three being located at a relatively low altitude in the sky and subject to interference from a nearby bright Moon. The final event occurs prior to dawn and is a convenient target for observers also wishing to view Hale-Bopp. 532 Herculina is a relatively large asteroid and being at a low altitude (12deg) casts a shadow some 1100km in width, potentially extending the full length of the UK. Expect the star to decrease six-fold in brightness if an occultation is seen. Observational details including recommended observing 'windows' are as follows: Object: 445 Edna Observing Window: 22:38 - 22:50 UT Star: PPM 68862 RA(2000): 3h 52m 40s Dec(2000): +32deg 24m 31s V Magnitude: 6.7 Decrease in Brightness: 8 mags Maximum Duration: 5 sec approx. Object: 2761 Eddington Observing Window: 03:53 - 04:43 UT Star: GSC 1904 1183 RA(2000):7h 10m 33s Dec(2000): +27deg 09m 23s V Magnitude: 12.2 Decrease in Brightness: 4 mags Maximum Duration: 14 sec approx. Object: 532 Herculina Observing Window: 05:42 - 06:02 UT Star: GSC 6266 2247 RA(2000):18h 26m 34s Dec(2000):-16deg 10m 37s V Magnitude: 10.2 Decrease in Brightness: 2 mags Maximum Duration: 6 sec approx. Results, positive AND negative should be reported to: rmiles@baa.u-net.com See details of other occultation events and finder charts for the 445 Edna and 532 Herculina events at: http://www.ast.cam.ac.uk/~baa/occ.html Guy M Hurst