Circular No. 4670 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Telephone 617-495-7244/7440/7444 (for emergency use only) TWX 710-320-6842 ASTROGRAM CAM EASYLINK 62794505 MARSDEN or GREEN@CFA.BITNET MARSDEN or GREEN@CFAPS2.SPAN V CORONAE AUSTRINAE W. A. Lawson, P. M. Kilmartin, and A. C. Gilmore, Mount John University Observatory, report preliminary photometry of a decline in brightness of this R CrB-type star: Oct. 5.49 UT, V = 10.02, B-V = +0.71; Oct. 21.36, 10.53, +0.73; Oct. 30.37, 11.04, +0.76. ASM 2000+25 P. A. Charles, Royal Greenwich Observatory, La Palma; and M. Kidger, Instituto de Astrofisica de Canarias, Tenerife, report: "We have discovered an optical modulation in the counterpart of the x-ray nova ASM 2000+25 (cf. IAUC 4600, 4609) at a period of 7.0 +/- 0.5 hr. This is based on 129 R-band and 36 Johnson-V CCD images obtained with the 1-m Jacobus Kapteyn Telescope on La Palma during the period July 29-Aug. 4. A modulation was also seen in data obtained with the same configuration on Oct. 18. The mean R magnitude was 15.9 in July and Aug. and 17.7 in Oct., with the modulation at a level of 0.15-0.20 mag and sinusoidal in Aug., somewhat less in Oct. This period is remarkably close to that of the orbital period of V616 Mon = A0620-00 and a search for an x-ray modulation at this period is urgent. Optical spectroscopy in a search for the secondary star should go ahead when the nova has reached quiescence, probably around the middle of next year." PERIODIC COMET TEMPEL 2 (1987g) Total visual magnitude estimates (cf. IAUC 4656): Sept. 29.77 UT, 8.7 (R. Haver, Rome, Italy, 15x80 binoculars); Oct. 9.10, 8.0 (R. Keen, Mt. Thorodin, CO, 8x40 binoculars); 14.08, 9.1 (G. R. Chester, Rixeyville, VA, 0.2-m reflector); 28.08, 9.5 (A. Hale, Las Cruces, NM, 0.41-m reflector); 31.11, 9.2 (C. S. Morris, Pine Mountain Club, CA, 0.26-m reflector). NOVA IN THE LARGE MAGELLANIC CLOUD 1988 No. 2 Visual magnitude estimates (cf. IAUC 4666) by R. H. McNaught, Siding Spring Observatory: Oct. 20.45 UT, 12.9; 20.69, 13.0; 21.73, 13.2; 23.74, 13.3; 28.50, 13.4. 1988 November 1 (4670) Daniel W. E. Green
Our Web policy. Index to the CBAT/MPC/ICQ pages.