------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 1510 2000 Apr 06 11.10UT 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 ------------------------------------------------------------------- OCCULTATION OF TYC 1389 0373 by 791 ANI, 2000 APRIL 7 Richard Miles reports: The following occultation event has a >90% probability that the shadow track will cross mid-/southern England. Please try to observe and time the disappearance and reappearance. If you are successful send me the details including precise location of your observing station. This medium-sized asteroid, some 107 km across, is predicted to occult the star, TYC 1389 0373 (V=10.2) on Friday evening as seen from Ireland, England/Wales, Belgium, The Netherlands and Germany. Details are as follows: Location of star: RA(2000): 08h 09m 21s Dec(2000) +21deg 47'07" Observational coverage should span the period 21:13-21:33 UT, with the expected mid-time (from mid-UK) = 21:23 UT. Event Rating: Highly Favourable based on recent update of the position of the predicted path (posted by Jan Manek on March 31), and size of object. The maximum duration of the event is expected to be relatively long, about 15 seconds. The star will dip in brightness by about five magnitudes (i.e. by a factor of 100). Note that seen from the UK, the event takes place at a high altitude above the horizon in the range, 46-52deg, and an azimuth of about 232 deg. The Moon will be 12% illuminated and some 61 degrees distant and so will not interfere with observations. Observers equipped with telescopes of 10 cm aperture or greater may wish to monitor this very close appulse / occultation. Jan Manek has pointed out that the 120 km shadow track could be anywhere along a strip of Europe about 400 km in width due to the 3.5 path width uncertainity (this is 4 times larger uncertainity than for the successful Pales event earlier this year). Ensure you have enough time to locate the correct star. The star is faint so a 20cm telescope would be needed for comfortable visual observation. Target star is in western Cancer, close to border with Gemini, only 25' NE of 5.3 mag star mui2 Cancri. There are 3 stars of very similar brightness (as target star) within 6' of target forming a nice triangle so they provide nice reference net. Editor: Richard has sent two map files which can be sent on request. Guy M Hurst