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                    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 269 (January 14, 2000)

0735-40 CGCS 1825 - NEW RED VARIABLE IN PUPPIS

D. Green, Central Bureau for Astronomical Telegrams, reports the following:
Paul Camilleri, Cobram, Victoria, Australia, has discovered a new variable,
likely a long period variable, in Puppis at magnitude 9.5 on three films
taken January 7.508 UT using an 85-mm camera lens.  Camilleri also observed
the star visually on Jan 8.47 at magnitude 9.5 with a strong red color.  Films
of his from late 1991 and early 1992 show nothing at the location down to
magnitude 12.

Camilleri notes that the star is a couple of arcminutes east of GSC 7648 819.
A precise position for this object was provided by G. Garradd, Loomberah, NSW,
Australia, from CCD images taken on Jan 8.50 UT as:

     R.A. = 07h 39m 04.40s     Decl. = -40 degrees 28' 47.0" (epoch 2000)

Additional observations of this new variable include: 1999 Jun 3.36 UT, <11
photographic, Camilleri; 1999 Jun 4.38, <11 photographic, Camilleri;
2000 Jan 8.50, 8.8 CCD (mean of 3 images), Garradd; 10.44, 10.8 visual,
M. Morel, Thornton, NSW, Australia.

Photoelectric photometry carried out on the star by A. Gilmore, Mount John
University Observatory, New Zealand, indicates that it is extremely red:
Jan 9.467 UT, 9.76 V, B-V = +4.40, V-R = +1.79, V-I = +3.27, airmass 1.08
(comparison stars Cousins' E304 and E348).

B. Marsden, Central Bureau for Astronomical Telegrams, notes that there is
a faint star at the position of the new variable in the Digital Sky Survey
and the USNO A2.0 Catalogue.  It is faint on the DSS, and in the blue at
magnitude 17.6, but is bright in the red at magnitude 11.2 (i.e., B-R = +6.4).

Garradd and F. Bateson, Royal Astronomical Society of New Zealand, forwarded
a message from M. Morel, Thornton, NSW, Australia, noting that this star
is CGCS 1825 in the second edition of C.B. Stephenson's "General Catalogue
of Cool Galactic Carbon Stars", 1989, Publ. Warner and Swasey Obs. 3, No. 2,
and is classified as a carbon star.

Observers are encouraged to monitor this variable now, while it appears to be
near maximum, and throughout its entire cycle, so that its nature may be
determined.  Because the star is so red, please be very careful in making your
observations that you do not look at the variable for any length of time.  Use
the quick-glance method to avoid a falsely-bright magnitude estimate caused by
the sensitivity of the human eye to red light.  If you carry out CCD photometry
of the star, it is strongly recommended that you use a Visual filter, because
of the red-light leak in the unfiltered CCD.

Accompanying is a "b" scale AAVSO preliminary chart showing the variable.
Please use it to observe 0735-40 CGCS 1825 and report your observations to
AAVSO Headquarters.  Please be sure to indicate which comparison stars you
used to make your estimates.

Congratulations to Paul on his latest discovery!

CHARTS AVAILABLE ON AAVSO WEB AND FTP SITES

Electronic copies of the chart for CGCS 1825 in Puppis mentioned in this
Alert Notice are available through our web site at the following address:

                         http://www.aavso.org

The chart may also be obtained directly from our FTP site:

       ftp.aavso.org (198.116.78.5), in /alerts/alert269

The answering machine at AAVSO Headquarters is on nights and weekends for
your convenience. Please call our charge-free number (888-802-STAR =
888-802-7827) 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.

If you need to change the email address this Alert Notice is sent to, or
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Many thanks for your valuable astronomical contributions and your efforts.

Good observing!

Elizabeth O. Waagen, Senior Technical Assistant
on behalf of
Janet A. Mattei, Director




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