THE ASTRONOMER Electronic Circular No 407 1990 Apr 29 15.16UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP, England. Telephone: (0256)471074 Int:+44256471074 Telex: 94082518 Answerback: TAGUY Microlink: MAG60138 JANET:GMH @ UK.AC.CAM.ASTRONOMY.STARLINK or GUYH@UK.AC.SUSSEX.CLUSTER --------------------------------------------------------------------- HUBBLE SPACE TELESCOPE The Space Telescope Science Institute reports that the orbiter Discovery was launched on Apr. 24.52 UT, and its crew successfully deployed the Hubble Space Telescope on Apr. 25.82 into an orbit with minimum and maximum altitudes of 613 and 615 km (331 and 332 nautical miles), respectively. The HST was developed by the National Aeronautics and Space Administration and the European Space Agency for scientific research by the international astronomical community. If nominal performance continues during initial verification activities for the HST observatory, the first cycle of General Observer observations will begin about the end of 1990 December. IAUC 5000 COMET AUSTIN (1989c1) The following post-perihelion precise positions have been reported: 1990 UT R.A. (1950) Decl. Observer Apr. 25.49375 0 34 56.36 +35 53 27.3 Helin 26.47083 0 29 57.87 +35 57 38.9 Bus 26.47986 0 29 55.09 +35 57 39.4 " 26.76775 0 28 26.12 +35 58 22.8 Okamura 26.76917 0 28 25.71 +35 58 22.8 " 26.77066 0 28 25.23 +35 58 23.2 " 26.77375 0 28 24.20 +35 58 24.3 " 26.77625 0 28 23.44 +35 58 24.8 " 26.77750 0 28 23.10 +35 58 24.4 " E. Helin, B. Roman, K. Lawrence, and R. Lopes (Palomar). 0.46-m Schmidt telescope. Measured by Roman. S. J. Bus (Lowell Observatory, Anderson Mesa Station). 0.33-m telescope. Measured by B. A. Skiff. Communicated by E. Bowell. Straight ion tail in p.a. 310 deg. S. Okamura (Kiso). The following orbital elements, by Dan Green, satisfy 57 observations 1989 Dec. 6-1990 Apr. 26 (mean residual 0".8): Epoch = 1990 Apr. 19.0 ET T = 1990 Apr. 9.96739 ET Peri. = 61.56934 e = 1.0002278 Node = 75.22965 1950.0 q = 0.3497735 AU Incl. = 58.95559 IAUC 5001 TA DATABASE The membership records have now been transferred to the Amstrad 2286 and I shall be grateful if subscribers will check address labels on any snail-mail they receive and advise of any amendments required. I am grateful to Nick James and Martin Mobberley for their invaluable help with this transfer work. I plan to reorganise databases on all existing TA catalogues and to expand this service to new areas during 1990. Guy M Hurst