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

			AAVSO ALERT NOTICE 178 (September 23,1993)

1425-50 NOVA LUPI 1993

We have been informed by our member William Liller, Vina del Mar, Chile, of his 
photographic discovery, using PROBLICOM, of a nova in Lupus at magnitude 8.0 (average 
of two photographs, TechPan film plus orange filter) on September 19.02 UT. The 1950 
position, precessed from the equinox 2000 measurements provided by R.H. McNaught and 
G.J. Garradd, Anglo Australian Observatory, is

		RA 14h 28m 26.04s	Decl. -50deg 57' 18.2"

A search by Liller of plates taken between January 1991 and May 4, 1993, revealed no star 
brighter than 11.5 at this position. McNaught and Garradd report that a visual check with 
ESO B and R and SERC J surveys show no candidate for this object to magnitude 17 and 
no star in the immediate vicinity displaying an obvious color (IAU Circular 5868).

Liller provides the following CCD(V) observations: Sep. 19.987 UT, 7.97; Sep. 20.994, 8.47. 
D. Overbeek, Edenvale, South Africa, reports N Lup 93 at visual magnitude 8.8 on Sep. 
23.72 UT. Liller further reports that a low-resolution spectrogram taken with an objective 
prism shows a nova spectrum similar to N Sgr 93; H-alpha and nebular lines features are at 
least twice as intense as the local continuum (IAU Circular 5868).

Please use the accompanying 'b' scale AAVSO chart prepared by C. Scovil in making 
observations of this new nova, and report your observations to AAVSO Headquarters. The 
answering machine is on nights and weekends for your convenience.

Our very sincere congratulations to Bill Liller for his second nova discovery within two 
days!

REVISED FINDER CHART FOR 1806-29 NOVA SAGITTARII 1993

Accompanying is the revised 'b' chart for Nova Sagittarii 1993 (with the main header 1808-
29 VZ Sagittani). The first version of this chart was distributed with AAYSO Alert Notice 
177. The position of the 9.1 star to the west of the nova has been revised, and comparison 
stars have been added with photovisual magnitudes of 9.5 (for the previously-indicated 9.1) 
and 10.0, thanks to measurements of a Stamford Observatory plate by C. Scovil. Please 
check your observations of Nova Sgr 93, and if they are affected by these changes, make 
any necessary revisions and re-submit them to Headquarters. We apologize for the error 
on the previous chart.

William Liller provides the following CCD(V) magnitudes for N Sgr 93: Sep. 17.058 UT, 
8.51; Sep. 18.015, 8.47; Sep. 19.041, 8.27; Sep. 20.017, 8.75; Sep. 20.988, 8.87. R. Royer, 
Lakewood, CA, reports N 5gr 93 at visual magnitude 9.1 on Sep. 23.12 UT. D. Overbeek, 
Edenvale, South Africa, also reports it at visual magnitude 9.1 on Sep. 23.72 UT.

SUCCESSFUL COMPLETION OF ORFEUS MISSION

We have been informed by Dr. Robert Stachnik, NASA's ORFEUS Program Scientist, that 
after its five-day mission the ORFEUS spacecraft was returned to space shuttle Discovery's
cargo bay on Sunday, September 19. He reports that:

"The overall observing efficiency was very high...in addition to the expected 
white dwarfs, chromospheric sources, etc., data were also obtained on 
cataclysmic variables in both temporary and permanent outburst states...an 
observation of Nova Sagittarii 1993, discovered on Wednesday, showed no 
significant FUV flux"

Later Dr. Stachnik sent the following electronic message to AAVSO:

"This is to express the thanks of the ORFEUS-SPAS team and the NASA 
Physics Division for the assistance of the AAVSO in connection with the 
recent flight of ORFEUS. The mission was highly successful and some of the
most exciting observations were the result of AAVSO efforts. While 
AAVSO is justly proud of its designation as an amateur organization, that 
designation is appropriate in only the most restrictive sense. The 
professionalism of your membership and of the Cambridge office is 
legendary. Thanks so much for your help."

We very much appreciate and thank our observers for the dedicated monitoring of ORFEUS 
observing targets and other cataclysmic variables, and for the timely phone calls that were 
vital to the success of the ORFEUS mission.

OUTBURST OF 0409-71 VW HYDRI

VW Hyi, which was reported in outburst in AAVSO Alert Notice 177, had a narrow outburst. 
It reached maximum on September 17.8 UT at magnitude 9.5, and by September 20.104 it 
had declined to magnitude 13.0. We thank Danie Overbeek, Jan Smit, and Jan Hers, all of 
South Africa, for their observations and for keeping us informed of the behavior of VW Hyi.

VW Hyi is scheduled to be observed at minimum with the Hubble Space Telescope on 
September 25. Please phone in your observations of VW Hyi to AAVSO Headquarters so 
we may provide optical data during HST observations.

Many thanks for your valuable observations and dedicated efforts.

Good observing!

Janet A. Mattei
Director

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