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

				AAVSO ALERT NOTICE 205 (April 4,1995)

OUTBURST OF 0749+22 U GEMINORUM

The dwarf nova-type cataclysmic variable U Geminorum is in outburst, as indicated by the following 
observations:

Mar 31.894 UT, 14.0, O. Midtskogen, Tranby, Norway (via B. Granslo); Apr 1.044, 13.9, R. Stewart, 
Fairlawn, NJ; 1.070,14.1, P. Dombrowski, Glastonbury, CT; 1.188,13.5, T. Hunter, Tucson, AZ; 1.146, 
14.0, CCDV R. Zissell, S. Hadley, MA; 1.198, 13.5, D. York, Abiquiu, NM; 1.233, < 13.8, W. 
Albrecht, Pahala, HI; 1.240, 13.8, York; 1.278, < 13.3, R. Royer; Lakewood, CA; 1.347, 13.6, Albrecht; 
1.844, 12.8, J. Ripero, Madrid, Spain (via W. Wamsteker); 1.860, 12.8, Midtskogen (via B. Granslo); 
2.005, 12.0, R. Raphael, S.W. Harbor, ME; 2.008, 12.5, B. Granslo, Aarnes, Norway; 2.023, 12.5, 
Dombrowski; 2.030, 12.4, Granslo; 2.035, 12.8, G. Dyck, Assonet, MA; 2.052, 12.4, J. Bortle, 
Stormville, NY; 2.079, 12.2, A. Dill, Wichita, KS; 2.084, 12.2, CCD-V Zissell; 2.111, 12.1, York; 2.150, 
11.72, CCD-V G. Emerson, Golden, CO; 2.154, 11.7, P. Robbins, Kansas City, KS; 2.181, 11.2, W. 
Dillon, Missouri City, TX; 2.185, 11.2, W. Clark, St. Louis, MO; 2.197, 11.54, CCD-V Emerson; 2.201, 
11.52, CCD-V Emerson; 2.212, 11.1, T. Burrows, Novato, CA; 2.253, 11.0, Royer; 2.267, 10.8, Burrows; 
2.346, 10.4, Burrows; 2.817, 9.3, H. Dahle, Oslo, Norway (via B. Granslo); 2.826, 9.2, G. Comello, 
Groningen, Netherlands; 2.861, 9.1, M. Gill, Birmingham, England (via G. Poyner); 2.868, 9.3, M. 
Westlund, Uppsala, Sweden; 2.910, 9.5, Schmeer; 2.917, 9.3, W. Hodgson, Stockport, England; 2.993, 
9.0, Raphael; 3.014, 9.3, Dombrowski; 3.022, 9.4, Stewart; 3.039, 9.1, H. Guidry, Littleton, NC; 3.042, 
9.2, P. Steffey, Daytona Beach, FL; 3.045, 9.2,C. Stephan, Sebring, FL; 3.053, 8.9, J. McKenna, Upper 
Montclair, NJ; 3.056, 8.8, C. Fausel, Jasper, IN; 3.061, 9.1, R. Hays, Worth, IL; 3.076, 9.1, R. Harvan, 
Leonardstown, MD; 3.078, 9.3, Bortle; 3.103, 9.3, Stewart; 3.113, 9.5, Clark; 3.150, 9.0, Burrows; 3.170, 
9.0, Dillon; 3.181, 9.5, Royer; 3.183, 9.3, M. Adams, Fort Worth, TX; 3.79, 9.0, L. Szentasko, Budapest, 
Hungary; 3.81, 9.1, G. Zajacz, Debrecen, Hungary; 3.9, 9.2, L. Kiss, Szeged, Hungary; 4.031, 9.2, 
Stephan; 4.168, 9.0, Burrows; 4.247, 9.3, Royer.

Thanks to very close monitoring by our observers around the world, the rise of U Gem to outburst was 
very well recorded.

In addition, Dr. R. Zissell, S. Hadley, MA, has been observing U Gem closely, and, in response to our 
request in AAVSO Alert Notice 204, he has obtained a series of CCD-V observations of the eclipses 
of U Gem, as given below:

Apr 2.084 UT, 12.2; .1507 12.1; .1660 11.80; .1675 11.75; .1772 11.73; .1987 11.70; .2089 11.64; .2178 
11.55; .9970, 9.763; .9980, 9.771; .9997, 9.776; Apr 3.0027, 9.746; .0043, 9.760; .0060, 9.750; .0076, 
9.728; .0093, 9.757; .0109, 9.749; .0125, 9.744; .0146, 9.719; .0280, 9.724; .0316, 9.721; .0537, 
9.704; .0731, 9.690; .0832, 9.699; .0960, 9.696; .1090, 9.681; .1207, 9.695; .1347, 9.719; .1464, 
9.718; .1492, 9.703; .1538, 9.712; .1577, 9.721; .1606, 9.694; .1635, 9.693; .1659, 9.728; .1675, 
9.733; .1689, 9.710; .1717, 9.719; .1728, 9.744; .1738, 9.739; .1750, 9.745; .1760, 9.728; .1770, 
9.728; .1780, 9.715; .1790, 9.719; .1800, 9.741; .1810, 9.720; .1823, 9.733; .1835, 9.719; .1845, 
9.723; .1857, 9.718; .1868, 9.745; .1881, 9.709; .1892, 9.708; .1902, 9.715; .1912, 9.702; .1922, 
9.677; .1950, 9.659; .2012, 9.705; .2063, 9.692.

The last outburst of U Gem reached maximum on August 23/24, 1994. Since that outburst, U Gem 
has been monitored very closely, with no observing gaps. The data file on U Gem in the AAVSO 
International Database goes back to 1910 and shows that this recent outburst interval is one of the 
longest since 1910, and is the longest since 1943 with no seasonal observing gap.

Observers are strongly recommended to monitor the present outburst of U Gem. Those who can are 
urged to go after the eclipses and the humps (see AAVSO Alert Notice 204) as U Gem starts to decline.

Please call in your observations of U Gem to AAVSO Headquarters, as there are several astronomers 
interested in this star, particularly in observing it with the Hubble Space Telescope once U Gem has
returned to minimum, and your timely observations will be important in scheduling the HST.

1900-O1 NOVA AQUILAE 1995

Astronomers C. G. Mason and R. D. Gehrz, University of Minnesota, and C. E. Woodward, 
University of Wyoming, have obtained infrared observations of N Aq 95 that indicate the recent dust 
formation around the nova (IAU Cirmilar 6154). They recommend close monitoring of this nova in 
case it fades quickly in brightness - by several magnitudes within a few days - due to the formation of 
an optically thick dust shell. This fading is followed by a slow brightening of the nova as the dust shell 
expands. The prototype showing this behavior was DQ Herculis (Nova Herculis 1934); a more recent 
example is V705 Cas (Nova Cassiopeiae 1993).

N Aq 95 has faded slowly from its discovery magnitude of 8.2 on Feb 9 to approximately 10.3, as the 
following most recent observations indicate: Mar 15.538, 9.7, R. Royer, Lakewood, CA; 17.449, 10.3, 
R. King, Duluth, MN; 22.551, 10.1, Royer; 23.5,10.3, P. Collins, Scottsdale, AZ; 29.521,10.5, Royer.

Observers are urged to keep a very close eye on N Aq 95, using the "d" scale chart distributed with 
AAVSO Alert Notice 200. Please telephone/email your observations of this nova to AAVSO 
Headquarters, and indicate which comparison stars you used.

REQUEST TO MONITOR 1544+28A R CORONAE BOREALIS

We have been requested to monitor R Coronae Borealis, the prototype of the R Coronae Borealis 
class, through May, so that astronomers observing with the International Ultraviolet Explorer (IUE) 
and studying the pulsation process in this star may correlate the IUE data with the optical data. Please 
monitor this bright star closely, and call in your observations of R CrB to AAVSO Headquarters. 
Please inform us immediately if R CrB starts to fade.

MONITORING OF 0900-31 T PYXIDIS

We have a standing request from astronomers at the Space Telescope Science Institute to keep a very 
close eye on T Pyx, and to inform them should the star go into outburst. The last outburst of T Pyx 
occurred in December 1966, when it reached magnitude 7.2. T Pyx has a star close by to the southwest 
that is a variable. Observers are thus urged to be extremely careful of their identification of T Pyx.

MONITORING OF THE OLD NOVA 0324 + 43 GK PERSEI

We also have a standing request to keep a close eye on GK Per, and to inform astronomers in 
different parts of the world when it starts to brighten. The last minor brightening of GK Per was in 
July 1989, when it reached magnitude 10.3.

The answering machine at AAVSO Headquarters is on nights and weekends for your convenience. 
Please call our charge-free number (800-642-3883) to report your observations. We also encourage 
observers to send observations by fax at b17-354-ObbS or by e-mail through the Internet at 
aavso@cfa.harvard.edu.

When telephoning in observations, please state the name of the star, the magnitude, and the time of 
the observation. The preferred time is either your local time (be sure to state the time zone and 
whether it is Standard or Daylight Savings Time) or Universal Time. You do not need to give the 
designation of the star. Please also include the comparison stars you have used in making the 
observation.

Many thanks for your dedicated efforts and valuable contributions, particularly in monitoring U Gem 
so closely and helping to record its rise to maximum so well.

Good observing!

Janet A. Mattei 
Director

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