THE ASTRONOMER Electronic Circular No 768 1993 Aug 16 20.10UT 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 ------------------------------------------------------------------- FIREBALL Christine Platt, Reading, UK reports a visual observation of a bright fireball, probably a Perseid of about magnitude -12 seen at approx 19.50UT on Aug 16. The object was first seen at about 30 degrees altitude in the North-East moving straight down to the horizon and flaring up with sparks before final extinction. The estimated duration was 3 seconds, suggesting it was relatively slow-moving. The fireball, of yellowish-white colour, was seen in strong twilight. If any other observers witnessed this event please e-mail results as soon as possible. GRO J0422+32 A. V. Filippenko and T. Matheson, University of California, Berkeley, report that the brightness of GRO J0422+32 appears to have increased significantly since the last reports in April. Preliminary calibration of spectra (range 310-1000 nm) obtained on Aug. 13 UT with the Shane 3-m reflector at Lick Observatory yields V = 14.7 +/- 0.5. Strong, broad Balmer absorption lines are visible in the rather blue continuum; H-alpha exhibits an emission component, as well. The object may have experienced a new accretion event at some time during the past four months. A. J. Castro-Tirado, Danish Space Research Institute, Lyngby; and J. L. Ortiz, Instituto de Astrofisica de Andalucia, Granada, report: "We have been observing the optical counterpart of the soft x-ray transient GRO J0422+32, discovered in 1992 Aug. CCD frames taken at the Spanish 1.52-m telescope at the German-Spanish Calar Alto Observatory have shown that GRO J0422+32 has undergone a dramatic and unexpected increase in brightness by 3.6 mag in the last three days. Preliminary magnitudes (+/- 0.2): Aug. 10.105 UT, V = 18.7; 13.17, 15.1. The object may be emitting strongly at high energies, therefore x-rays and gamma-ray observations should be very valuable. Spectroscopic and photometric observations at all wavelengths are encouraged." IAUC 5842 P.Garnavich, Dominion Astrophysical Observatory, has subsequently sent the following report to us: "The X-ray nova GRO-J0422+32 appears to, again, be in outburst. CCD photometry obtained at the Manastash Ridge Observatory of the University of Washington gives the following preliminary V magnitudes: UT Date V mag Aug 10.476 17.8+-0.1 Aug 11.470 15.83+-0.04 Aug 12.455 15.68+-0.03 Aug 13.490 15.32+-0.03 This object is already on the Recurrent Objects Programme of the UK Nova/Supernova Patrol and further observations are urgently needed. DX ANDROMEDAE Further estimates of the current outburst (cf E767): Aug 13.030UT, 13.2 (G.Poyner, Birmingham, UK); 13.89, 11.9 (M.Westlund, Sweden); 13.94, 12.4 (B.Granslo, Norway); 13.99, 12.1 (H.Bengtsson, Sweden); 14.88, 11.9 (Bengtsson).