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

			AAVSO ALERT NOTICE 150 (October 31, 1991)


RARE OUTBURST OF 2137+48 V1251 CYGNI

We have been informed by G. Hurst (UK) and P. Schmeer (Germany) that the cataclysmic 
variable 2137+48 V1251 Cygni is in outburst, as indicated by the following observations:

Oct.	15.90 UT	<14.2	(P. Schmeer)
	25.54		12.4 	(M. Moriyama, Japan - via T. Kato and Hurst)
	26.89		12.4 	(Moriyama)
	26.833		12.7 	(Schmeer)
	27.880		12.5 	(Schmeer)
	29.755		12.6 	(Schmeer)
	30.06		12.8	(C. Scovil)

This is apparently the fIrst observed outburst since 1963 when it brightened to 
photographic magnitude 12.5, as reported by R. Weber (1966) in the Information 
Bulletin of Varlable Stars (IBVS) No. 123. This star has been in our program 
since the mid-1980's and no outburst observations have been recorded.

Please monitor V1251 Cyg closely, using the accompanying chart prepared by C. 
Scovil with a CCD (V) sequence obtained by T. Kato of Kyoto University, Japan, 
and transmitted to us by P. Schmeer.


LARGE AMPLITUDE HIPPARCOS STARS IN NEED OF MORE OBSERVATIONS

In order for us to provide the data support needed for the observations of long 
period variable stars with the HIPPARCOS satellite, the following stars need more 
observations at this time:

Desig.		Star		Range			Design.		Star		Range
0004-86		RU Oct		10.2 - <13 P		2018+00		V865 Aql	11.4 - 14.5 P
0024-38A	T Scl		9.2 - 13.0		2022-40		U Mic		8.8 - 14.0
0329-16		RT Eri		8.5 - 12.9 P		2034-29		R Mic		9.2 - 13.4
0413-18		RS Eri		9.2 - <12.8P		2101-24		V Cap		8.2 - 14.4
0445-55		SU Dor		9.3 - 14.5		2116-15		T Cap		9.5 - 13.9
0450-07		SX Eri		9.3 - <13.6		2116-42		W Mic		10.3 - 15.5P
0509-64A	U Dor		9.2 - <15 P		2117-41		V Mic		9.4 - 14.0
0657-66		T Vol		9.7 - <13.9 P		2129+02		WW Aqr		10.5 - 14.5 P
0706-19A	SY CMa		10.4 - 14.3 P		2213-21		X Aqr		8.3 - 14.4
0707+14		VX Gem		10.8 - <15.1 P		2217-22		RT Aqr		8.8 - 13.1
0717+13		V Gem		8.5 - 14.2		2219-38		T Gru		8.6 - 11.5
0721+41		VX Aur		9.6 - <12.5 P		2241-87		RT Oct		10.4 - 14.6 P
0753-43		SU Pup		9.3 - <14.0 P		2245+17		SX Peg		9.7 - 15 P
2011-21		RT Cap		8.9 - 11.7 P		2353-53		Z Phe		10.0 - <15.0 P

Observers worldwide participating in the HIPPARCOS mission are requested 
to monitor these stars once a week, if possible, and report the observations 
monthly to Headquarters.

The HIPPARCOS mission, in operation for over two years, has been obtaining 
valuable astrometric and photometric data on these stars. The visual 
observations provided by observers worldwide have been crucial in checking 
and refining the ephemerides of these stars used by the satellite. We extend 
the appreciation and thanks of the HIPPARCOS Input Catalogue and Science 
Teams to all the observers.

UPDATES ON THE ACTIVITIES OF STARS REPORTED IN ALERT NOTICE 149 1825-29 V1017 SAGITTARII

After a short standstill, at around 12.5 magnitude, this symbiotic star is now 
slowly brightening as reported by D. Overbeek and D . York. On Oct 26.07 UT it 
was 11.5 (York).

1809-29 VZ SAGITTARII

This R Coronae Borealis star undergoing a minimum, after reaching magnitude 12.6 on 
Oct. 1.5 UT (T. Cragg), has started to brighten as reported by D. Overbeek, T. 
Cragg, and D. York. On Oct 26.07 UT it was 10.9 (York).

V348 SAGITTARII

This interesting variable star has been varying between magnitudes 13.4 and 13.7 
as reported by D. Overbeek and D. York.

Clear skies and good observing!

Janet A. Mattei
Director

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