[IAUC] CBET 1591: 20081201 : PROBABLE NOVA IN SAGITTARIUS

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                                                  Electronic Telegram No. 1591
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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PROBABLE NOVA IN SAGITTARIUS
     W. Liller, Vina del Mar, Chile, reports his discovery of an apparent
nova (mag approximately 8.0) on two photographs taken with Tech Pan film
and an orange filter on Nov. 29.040 UT; the variable was also present on
Nov. 23.037 at approximate magnitude 10.3 but was not visible (mag > 11.0)
on Nov. 20.035.  The new object is located at R.A. = 18h22m.0, Decl. =
-28d03' (equinox 2000.0).  Liller adds that a pair of objective-grating
spectrograms (yielding 44.0 nm/mm at H-alpha) taken on Nov. 30.013 clearly
shows that the variable has a very strong H-alpha emission with a FWHM of
approximately 2500 km/s, quite typical of a classical nova several days
after peak brightness.  Because of the low altitude (about 17 degrees) of
the variable suspect at the time of observation, the extinction in the
blue-green portion of the spectra amounted to an estimated two magnitudes;
for this reason, as well as to eliminate overlapping orders, an orange
filter was used (with Tech Pan film).  No other lines were visible.
A direct photograph (orange filter, Tech Pan film) taken at Nov. 29.999
shows that the apparent nova's approximate magnitude was 7.8, virtually
unchanged from that of the discovery image.  Note that the new object is
located 1.4 arcminutes south-southeast of the tenth-magnitude star GSC
6852-3160.


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                         (C) Copyright 2008 CBAT
2008 December 1                  (CBET 1591)              Daniel W. E. Green