Skip to main content

Alert Notice 205: Outburst of 0749+22 U Geminorum AND 1900-01 Nova Aquilae 1995 AND Request to monitor 1544+28a R Coronae Borealis AND Monitoring of 0900-31 T Pyxidis AND Monitoring of the old nova 0324+43 GK Persei [V1425 Aql]

The membership database is currently undergoing upgrading/testing. Web functions that involve an interface with the member database (webobs, etc.) may experience intermittent problems. We hope to have this issue resolved within 24 hours (by 5pm Eastern Time on October 1st or 12:00 UT). Thank you for your patience.

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.

1900-01 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 Aql 95 that indicate the recent dust
formation around the nova (IAU Circular 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 Aql 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.

Chart links are obsolete; 11/2013 create charts using VSP at http://www.aavso.org/vsp

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

---------------------------------------------------‬
SUBMIT OBSERVATIONS TO THE AAVSO

Information on submitting observations to the AAVSO may be found at‭:‬
http‭://‬www.aavso.org/webobs

ALERT NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION

An Alert Notice archive is available at the following URL‭:‬
http‭://‬www.aavso.org/alert-notice-archive

Subscribing and Unsubscribing may be done at the following URL‭:‬
http‭://‬www.aavso.org/observation-notification#alertnotices

-------------------------------------------------

Please support the AAVSO and its mission -- Join or donate today:
http://www.aavso.org/apps/donate/

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