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

			AAVSO ALERT NOTICE 182 (March 11, 1994)

1229+08 SUPERNOVA 1994D IN NGC 4526

We have been informed by the Central Bureau for Astronomical Telegrams (IAU 5946 and 
Nova Network) that R. R. Treffers, A. V. Filippenko, and S. D. Van Dyke (University of 
California at Berkeley) and M. W. Richmond (Princeton University) reported the discovery 
of a supernova in NGC 4526 (R.A. 12h 31m 31s Dec.+07 58.5', epoch 1950), located 9" 
west and 7" north of the galaxy nucleus. "The object was found on March 7 UT (R=15.2 
magn.) during the Leuschner Observatory Supernova Search, which uses an automated 
0.76-m telescope equipped with the Lawrence Berkeley Laboratory CCD camera. 
Confirmation was made with an image taken through thin fog on March 9, and the object 
appeared to be brighter than on March 7. It could not be detected to a limiting magnitude 
of R = ~17 on March 1. Inspection of spectra ...reveals that the supernova is of Type Ia, 
probably about 1 week prior to maximum brightness ...The continuum is very blue. This 
supernova could reach magnitude 11 to 12, since the parent galaxy is in the Virgo Cluster."

Accompanying is a finder chart for this galaxy and the surrounding field from the 
Thompson and Bryan Supernova Search Charts (1989). The comparison star magnitudes 
are all photoelectric (V) magnitudes and are from Hanes gi -41. 1976, Month. Not. Royal 
Astron. Soc., 177, 653; Kilkenny and Malcolm 1984, MNRAS 209, 169; and Geneva 
Observatory, Grenon M. et al.

Also accompanying are two CCD images of NGC 4526 showing the supernova, provided by 
M. W. Richmond and A. V. Filippenko.

Below are observations reported to the AAVSO and the Central Bureau of Astronomical 
Telegrams:

Mar 9.90 UT, 13.5 (J.-C. Merlin, Le Creusot, France; photovisual); 9.901, 13.7 (B. H. 
Granslo, Sollihoegda, Norway); 9.932, 13.3 (H. Dahle, Oslo, Norway); 10.885, 12.9 (O. 
Midtskogen, Tranby, Norway); 10.961, 12.5 (G. M. Hurst, Basingstoke, England); 11.548, 
12.8 (Y. Sekino, Kanagawa, Japan).

Please monitor the supernova closely and report your observations, giving the exact time to 
the minute, to AAVSO Headquarters using our charge-free number (1-800-642-3883). Be 
sure to indicate the comparison stars you have used in making your estimates.

1844-21 NOVA SAGITTARII 1994???

P. M. Kilmartin (Mt. John University Observatory, Christchurch, New Zealand) and B. 
Skiff (Lowell Observatory, AZ) have provided the following precise measurement for N 
Sgr 94 (IAU Circular5944):

R.A. 18h 5Om 37s Dec. -21deg 23'29" (epoch 2000),

which precesses to

R.A. 18h 47m 37s Dec. -21deg 27'02" (epoch 1950).

B. Skiff identifies a star of B magnitude 18 and R magnitude 16 as the suggested promising,,, 
candidate for this nova. N Sgr 94 has dropped significantly from the beginning of March to 
date, as indicated by the following observations reported to the AAVSO:

Mar 2.0 UT, 8.2 (D. Overbeek, Edenvale, S. Africa); 4.49, 8.6 (W. Dillon, Missouri City, 
TX); 5.0, 8.5 (Overbeek); 5.20, 8.6 (M. Zanotta, Laino, Italy); 5.54, 9.4 (P. Collins, 
Scottsdale, AZ); 6.42, 9.8 (P. Walker, Middlebury, VT); 7.0, 9.0 (Overbeek); 7.0, 9.2 (J. 
Smit, Waverley, S. Africa); 8.48,10.9: (R. King, Duluth, MN); 9.48, 11.0 (King); 10.46,10.9: 
(Dillon); 11.1, 11.0 (Smit); 11.013, 10.8 (Overbeek); 11.065, 10.8 (Overbeek).

R. M. Wagner, Lowell Observatory, reports that the spectrum of this object taken on Mar. 
4 by R. Bertram does not look like a nova spectrum. The continuuum is very red, with a 
"very narrow H-beta emission line" and many narrow absorption lines. He comments that 
this object may not be a nova but a long period variable (Nova Network).

This is certainly a very interesting object that deserves very close monitoring! Please 
monitor it whenever possible and report your observations to HQ.

Many thanks for your efforts and valuable astronomical contributions.

Janet A. Mattei 
Director

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