Alert Notice 220: Observations of 1058+38 Markarian 421 with Hubble Space Telescope AND Outburst of 0324+43 GK Persei AND 1813+49 AM Herculis may be fading from high state AND 1834-23 V348 Sagittarii to be observed with Hubble Space Telescope

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

AAVSO ALERT NOTICE 220 (April 3,1996)

OBSERVATIONS OF 1058+38 MARKARIAN 421 WITH HUBBLE SPACE TELESCOPE

Astronomers at Space Telescope Science Institute have requested our assistance in the
multiwavelength observing campaign they have planned for the object Markarian 421.
Their campaign will utilize four space satellites - XTE (X-ray Timing Explorer), ISO
(Infrared Satellite Observatory), IUE (International Ultraviolet Explorer), and ROSAT
(ROentgen SATellite) - and will take place from April 7 through April 20. Visual
observations, unfiltered CCD observations, and, particularly, B and V filtered CCD
observations will be very important to the successful correlation of the multiwavelength
data.

Please monitor Mark 421 closely from April 7 through April 20, and report your
observations to AAVSO Headquarters. An e' scale AAVSO preliminary chart of Mark
421 is enclosed for your use.

OUTBURST OF 0324+43 GK PERSEI

The old nova GK Per, presently undergoing a minor outburst (see AAVSO Alert Notice 219),
has reached maximum brightness after a slow rise, as the following recent observations
indicate:

Feb 28.5000 UT, 12.0, J. McKenna, Upper Montclair, NJ; 28.838, 12.1, G. Poyner, Birmingham, England; 28.977, 12.0, P. Schmeer, Bischmisheim, Germany, 29.0188, 12.0, G. Chaple, Townsend, MA; 29.0764, 12.1, A. Dill, Wichita, KS; 29.1500, 12.2, R. Royer, Lakewood, CA; 29.8, 12.0, M. Verdenet, Bourbon-Lancy, France; 29.866, 12.1, M. Westlund, Uppsala; 29.87, 12.2, J. Ripero, Madrid, Spain; Mar 1.0257, 11.8, McKenna; 1.1229, 12.0, S. O'Conner, Montreal North, Quebec; Canada; 1.4667, 11.8, S. Sakuma, Kawasaki, Japan; 1.52, 11.6, G. Dyck, Assonet, MA; 1.819, 12.1, A. Diepvens, Balen, Belgium; 1.857, 11.5, Ripero; 1.9785, 12.0, M. Biesmans, Essen, Belgium; 2.052, 12.0, J. Holtz, Coraopolis, PA; 2.1764, 11.9, T. Burrows, Novato, CA; 2.2174, 12.0, W. Dillon, Missouri City, TX; 2.4069, 11.8, Sakuma; 2.787, 11.9, Schmeer; 2.85, 11.5, J. Gunther, St. Oze, France; 3.1139, 11.9, M. Heifner, Denver, CO; 3.4014, 11.8, Sakuma; 3.52, 11.8, Dyck; 3.790, 11.7, Diepvens; 3.801, 11.8, Schmeer; 3.812, 11.5, Ripero; 4.0132, 11.8, Chaple; 4.0146, 12.0, McKenna; 4.1458, 11.9, Burrows; 4.4035, 11.9, Sakuma; 5.0035, 11.9, McKenna; 5.0139, 11.9, Chaple; 5.4104, 11.9, Sakuma; 5.8264, 11.8, M. Kohl, Laupen, Switzerland; 6.1146, 12.0, Royer; 6.1708, 11.9, Burrows; 6.7993, 11.9, Kohl; 7.7868, 12.0, Kohl; 7.807, 11.4, Schmeer; 7.8576, 11.7, Westlund; 8.0292, 11.9, M. Komorous, London, Ontario, Canada; 8.0424, 11.7, R. Hays, Worth, IL; 8.1083, 11.6, Dillon; 8.1792, 11.5, Burrows; 8.785, 11.5, Diepvens; 8.7861, 11.6, Kohl; 8.81, 11.6, B. Granslo, Fjellhamar, Norway; 8.811, 11.5, Schmeer; 8.85, 11.0, Verdenet; 8.8715, 11.6, Westlund; 9.1056, 11.8, Dill; 9.789, 11.6, Dill; 9.815, 11.6, Schmeer; 9.844, 11.1, R. Szabo, Ajka, Hungary; 9.85, 11.1, Verdenet; 9.882, 11.5, Granslo; 10.0090, 11.8, McKenna; 10.0313, 11.0, Chaple; 10.0444, 11.0, Connor; 10.0507, 11.3, Hayes; 10.0549, 11.3, Komorous; 10.0986, 11.6, R. Harvan, Leonardstown, MD; 10.1056, 11.2, W. Bailey, Toney, AL; 10. 1264, 11.6, Dillon; 10. 1403, 11.0, Heifner; 10. 1479, 11.8, Dill; 10.7785, 11.6, Kohl; 10.814, 11.2, Schmeer; 10.901, 11.6, Diepvens; 10.9715, 11.1, Biesmans; 11.029, 11.2, McKenna; 11.0347, 11.1, O'Conner; 11.0576, 11.2, Hayes; 11. 1375, 11.6, Bailey, 11.806, 11.2, Schmeer; 11.869, 11.6, Diepvens; 11.98, 11.1, Granslo; 12.0396, 11.0, Komorous; 12.0417, 11.3, Hayes; 12.1285, 11.0, Ditlon; 12.7882, 11.5, Kohl; 12.821, 11.2, Schmeer; 12.894, 10.9, Granslo; 13.008, 11.2, McKenna; 13.1049, 11.0, Heifner, 13.810, 11.0, Diepvens; 13.8479, 10.9, Kohl; 14.796, 11.1, Diepvens; 14.802, 11.0, Schmeer;15.2813, 10.9, Royer;15.817,11.0, Schmeer; 16.0542, 11.1, C. Stephan, Sebring, FL; 16.1028, 10.7, Heifner; 16.1139, 11.5, W. Kaminski, Fairburn, SD; 16.1750, 10.9, Burrows; 17.0215, 10.7, Komorous; 17.13, 10.7, K. Millyard, Toronto, Ontario, Canada; 17.4229,10-5, J. Griese, Rocky Hill, CT; 17.827, 10.9, Poyner; 17.8854, 10.6, K. Medway, Southampton, England; 18.016, 11.08 CCDV, R. Zissell, S. Hadley, MA; 18.0521, 11.2, Stephan; 18.1632, 11.0, Burrows; 18.847, 11.0, L. Jensen, Farum, Denmark; 18.9736, 10.7, Westlund; 19.0042, 10.6, Chaple; 19.0139, 10.7, O'Conner; 19.03, 10.8, Dyck; 19.1979, 10.7, G. Hanson, Cave Creek, AZ; 19.8, 10.7, Gunther; 19.801, 11.2, Jensen; 19.823, 10.9, P. Skalak, Czech Republic; 20.0090, 10.7, O'Conner; 20.1792, 11.0, Hanson; 20.788, 10.5, Skalak; 20.80, 10.5, Verdenet; 21.0910, 10.7, Dill; 21.1632, 10.6, Burrows; 22.0910, 10.5, Hayes; 22.1424, 10.1, Dillon; 22.1618, 10.5, Burrows; 23.1056, 10.3, Dillon; 23.1708, 10.6, Burrows; 23.8, 10.5, Verdenet; 23.812, 10.4, Schmeer, 24.0285, 10.7, Komorous; 24.1674, 10.4, Burrows; 24.815, 10.4, Schmeer; 25.0014, 10.6, McKenna; 25.83, 10.2, G. Comello, Groningen, Netherlands; 26-808,10.5, Jensen; 26.82, 10.3, Comello; 27.0167, 10.3, McKenna; 27.1722, 10.6, Hanson; 27.833, 10.2, Medway; 29.0333, 10.6, O'Conner; 29.1701, 10.4, Burrows; 30.0306, 10.7, Komorous; 30.1576, 10.4, Burrows; 31.1083, 10.3, Dillon; 31.1625,10.6:, Burrows; Apr 1.897, 10.8, Poyner.

With the assistance of the above observations, the XTE satellite has observed GK Per four
times. It is scheduled to make one last observation, during the outburst decline. Please
continue to monitor GK Per and report your observations to AAVSO Headquarters.

1813+49 AM HERCULIS MAY BE FADING FROM HIGH STATE

An international observing campaign on the prototype magnetic cataclysmic variable AM
Her was announced in AAVSO Alert Notice 218. Activity in this star was announced in
AAVSO NewsFlash No. 7, and the observations reported there as well as those received
since indicate that AM Her may be fading from its bright, high state, as the following
observations indicate:

Mar 6.5625 UT, 13.2, R. Royer, Lakewood, CA; 14.4285, 13.3, M. A. Komorous, London,
Ontario, Canada; 16.3993, 13.3, Komorous; 20.1701, 13.0, M. Kohl, Laupen, Switzerland;
22.1396, 13.3:, S. Brincat, Sangwann, Malta; 24.4021, 13.3, J. Griese, Rocky Hill, CT;
25.3153,13.4, Griese; 27.028,13.2, L. T. Jensen, Farum, Denmark; 27.339,13.50 CCDV, R.
Zissell, South Hadley, MA; 27.3743,13.5, Komorous; 28.226,13.70 CCDV, Zissell; 30.3243,
13.7, Komorous; 30.365,13.8 CCDV, Zissell; 31.274,13.5 CCDV, Zissell.

If AM Her is indeed fading, multiwavelength observations will be carried out, so your
observations at this time are extremely important. Please monitor AM Her and report
your observations to AAVSO Headquarters.

1834-23 V348 SAGITTARII TO BE OBSERVED WITH HUBBLE SPACE TELESCOPE

The interesting R CrB variable V348 Sgr, presently at its maximum brightness of
approximately magnitude 12.1 as reported by D. Overbeek, Edenvale, South Africa, is
scheduled to be observed at the end of April with the Hubble Space Telescope.

Please monitor V348 Sgr and report your observations to AAVSO Headquarters,
particularly if you see it beginning to decline.

CHARTS AVAILABLE ON AAVSO FTP SITE AND AAVSO HOME PAGE

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

Electronic copies of the AAVSO chart of Mark 421 mentioned in this Alert Notice are
available from our FT? site:

ftp.aavso.org (198.116.78.2), in /pub/alert220

The charts have also been placed on our home page:

http:/ /www.aavso.org

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 to 617-354-0665 or
by e-mail through the Internet to observations@aavso.org.

Many thanks for your valuable astronomical contributions and your efforts.

Good observing!

Janet A. Mattei
Director

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