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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
					Tel. 617-354-0484 FAX 617-354-0665
					
					
				AAVSO ALERT NOTICE 149 (October 1, 1991)
				
OUTBURST OF 1825-29 V1017 SAGlTIARII

John Bortle has alerted us to the brightening of VI017 Sgr, classified as a 
symbiotic star in the fourth edition of the General Catalogue of Variable 
Stars, as indicated by the following observations made by him and confirming 
observations made by David York and Charles Scovil:

Sep 13.1 UT < 13.0 Bortle	Sep 29.01012.6 Bortle	Sep 30.015 12.6 Bortle	Oct 1.02 12.5 Scovil
Sep 28.033 12.6 Bortle 		Sep 29.104 126 York		Sep 30.104 12.5 York

This star was reported on July 7.7 at magnitude 13.5 by TIDl Cooper and on 
July 19.7 at 13.5 by Danie Overbeek. Danie reports that VI017 Sgr was oscillating 
between 13.3 and 13.5 between Aug 2 and Sep 17, as 27 observations made by him 
indicate. On Sep 29.74 Danie independently observed VI017 Sgr at 13.1 and on 
Sep 30.74 at 12.8.

VI017 Sgr has had three recorded outbursts: in 1973, when the star reached about 
10th magnitude; in 1919, when it was reported at magnitude 7.2 on Harvard photographic 
plates; and 1901, when it reached about magnitude 10.8. The rise to maximum is slow. 
It is interesting to note that the interval between the present outburst and the 
1973 one is 18 years, between 1973 and 1919, 54 years (3 times 18), and between 1919 
and 1901 18 years. The third edition of the GCVS classified VI017 Sgr as a recurrent 
nova.

Accompanying is an "e" scale chart for VI017 Sgr. Observers are urged to monitor it 
and to inform us of its behavior.

1834-23 V348 SAGlTIARII

This interesting variable, classified as Unique and showing R Coronae Borealis-type 
behavior, is reported by Danie Overbeek to be brightening. On Sep 29.74 he 
observed it at magnitude 13.7, and on Sep 30.74 at 13.7. This star has been at 
minimum ( < 15.0) since February 1991. Usually the maximum is about magnitude 11.8.

Please use the accompanying "f" scale chart to observe V348 Sgr and report your 
observations to AA VSO Headquarters.

FADING OF 1808-29 VZ SAGITTARII

This R Coronae Borealis star has started to fade, as indicated by the following observations:

Sep 1.86 UT 10.4 A. Pereira		Sep 29.0 12.2 Bortle	Sep 29.712.0 Overbeek	 
Sep 30.712.0 Overbeek			Sep 26.83 < 11.7 ( - 1201) Pereira


Please observe this star with the accompanying "e" scale chart, and report your 
observations to AAVSO Headquarters. The Headquarters answering machine is on 
evenings and weekends (617-354-0484).

ACKNOWLEDGEMENTS AND REMINDERS

We extend the sincere thanks of the astronomers monitoring dwarf novae during 
the recent IUE observing run (see AAVSO Alert Notice 148). To those observers 
who kept a close eye on dwarf novae and called Headquarters, your information 
was very much appreciated by the astronomers, and of course, by us.

Reminder: Please keep an eye on the 10 high-galactic-latitude cataclysmic 
variables for which astronomers observing with the IUE have a standing request 
to be alerted when any of them go into outburst (see AAVSO ALert Notice 145).

As always, many thanks for your efforts and very valuable contributions. 
Good observing!

Janet A. Mattei
Director

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