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		THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS 
			25 Birch Street, Cambridge, MA 02138 USA
		   BITNET: aavso@cfa8 SPAN: nssdca::cfa8::aavso 
			INTERNET: aavso @cfa0.harvard.edu 
		   Tel. 617-354-0484	FAX 617-354-0665


		AAVSO ALERT NOTICE 167 (February 1, 1993)

THE SYMBIOTIC STAR 1810-00 FG SERPENTIS (AS 296)

FG Serpentis = AS 296 is a symbiotic system consisting of a hot compact primary and a 
late type giant secondary. It varies between magnitudes 12 and 9.8 (V). Since its recent 
outburst in 1988, it has been monitored closely both by professional and amateur 
astronomers. Munari et. al. (Astr. Journ., 104, 262; 1992) give a very good description of its 
multiwavelength behavior and its two post-outburst suggested eclipses, separated by 650 
days. Its next possible eclipse is predicted to occur in June 1993.

We have been requested to monitor this interesting system closely in the coming months 
both for the forthcoming predicted eclipse and also a possible pre-eclipse dip in the light 
curve, which had been observed before.

Please use the accompanying RASNZ chart with letter sequence added at AAVSO 
Headquarters. Please report your observations monthly in your regular monthly report, 
using this letter sequence and assuming 10 steps between lettered stars.

FORTHCOMING OUTBURST OF 0749+22 U GEMINORUM

Several astronomers scheduled to observe this dwarf nova with various space satellites, 
including EUVE, have requested to be informed when U Gem has its next outburst, 
predicted for the coming weeks. Its last outburst was in late August and early September, 
1992, when the star reached magnitude 9.3 at maximum, and stayed brighter than 
magnitude 11 for 12 days.

Please monitor this dwarf nova and call in your observations to Headquarters if you 
observe it at 13.5 magnitude or brighter. Please call in your observations throughout the 
outburst so we may monitor its shape and duration for astronomers interested in its decline 
from outburst.

The Headquarters answering machine is on weekends and nights. Observers in the USA 
can call in using the 800-number (toll-free) added to AAVSO Headquarters for the EUVE 
mission. The AAVSO's 800 number is:

			800-642-EUVE (617-642-3883)

For our observers outside the USA, please use our regular telephone number (617-354-
0484). We will reimburse telephone charges for reporting your observations on U Gem or 
other stars in the EUVE observing program.

Thank you very much for your observing efforts and contributions.

Clear skies! Good Observing!

Janet A. Mattei 
Director

Keywords:
AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484