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Alert Notice 288

              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 288 (August 27, 2001)

1818-30B  NOVA SAGITTARII 2001 NO. 2

We have been informed by the Central Bureau for Astronomical Telegrams (IAU
Circular 7692) that Alfredo Pereira, Cabo da Roca, Portugal, visually
discovered an apparent nova in Sagittarius at magnitude 7.6 on Aug. 26.866 UT
during his regular patrol with 14x100 binoculars.  Nothing was visible at the
location of the nova down to magnitude about 8.5 on Aug. 21.9 and 22.96 UT or
down to magnitude about 7.5-7.8 on Aug. 25.95 UT.  A. Hale, Cloudcroft, NM,
reported nothing was visible at the nova's location on the Digitized Sky
Survey.

C. Jacques, Belo Horizonte, Brazil, measured CCD frames taken by G. Nappi
on Aug. 27.00 UT at the request of the Central Bureau, and reports the position
of the star as:

      R.A. = 18h 24m 46.04s      Decl. = -30 degrees 00' 41.1"     (2000)

Observations submitted to the AAVSO (all except Mattei, Scovil, Griese, and
Reszelski were submitted via IAU Circular 7692) include: Aug. 26.913 UT, 7.3,
A. Pereira, Cabo da Roca, Portugal; 26.930, 7.4, Pereira; 26.940, 7.4, Pereira;
26.967, 7.2, Pereira; 26.996, 7.2:, Pereira; 27.10, 7.29 CCD(V), M. Mattei,
Littleton, MA (using 135-mm camera lens); 27.1007, 6.4, C. Scovil, Stamford,
CT; 27.1021, 6.6, J. Griese, Rocky Hill CT; 27.18, 7.4, A. Hale, Cloudcroft,
NM; 27.339, 7.46 PEP(V), P. M. Kilmartin, Mt. John Observatory, University of
Canterbury (using 0.6-m f/16 reflector and reference stars Cousins E745 and
E746); 27.353, 7.51 PEP(V), Kilmartin; 27.369, 7.58 PEP(V), Kilmartin; 27.375,
7.59 PEP(V), Kilmartin; 27.38, 8.0, A. Jones, Nelson, New Zealand; 27.815, 7.9,
M. Reszelski, Szamotuly, Poland.

We will be creating a page on N Sgr 01-2 on our website which we will update
every weekday with the observations received.  If you have items such as
images, spectra, etc. you would like to contribute to the page, please email
them to us.

Accompanying is an AAVSO 'b' scale preliminary chart of N Sgr 01-2 prepared by
C. Scovil.  Please use this chart to observe the nova, and report your
observations of 1818-30B N SGR 01-2 to AAVSO Headquarters, making sure to
indicate which comparison stars you used.

Congratulations to Alfredo on his latest discovery!

0329-36B  SUPERNOVA 2001DU IN NGC 1365 IN FORNAX

We have been informed by the Central Bureau for Astronomical Telegrams (IAU
Circular 7690) that Robert Evans, Hazelbrook, New South Wales, Australia,
visually discovered an apparent supernova in NGC 1365 on Aug. 24.7 and 25.7 UT,
using a 0.31-m reflector, at magnitude about 14.0.  Nothing was seen by Evans
at the location on Aug. 23.7 UT under poorer observing conditions.

CCD confirmation was obtained by G. Bock and P. Marples, Edens Landing,
Queensland, Australia, on an image taken Aug. 24.79 UT, using a 0.25-m
Schmidt-Cassegrain reflector, showing SN 2001du at CCD magnitude about 14.1.

SN 2001du, according to Evans located about 90" west and 10" south of the
nucleus of NGC 1365 and about 20" west of a 15.5-magnitude foreground star,
was measured by Bock at position:

        R.A. = 03h 33m 28.7s       Decl. = -36 degrees 08' 32"      (2000)

G. Garradd, Loomberah, New South Wales, Australia, reports that the supernova
is located at the western end of the galaxy's bar and is superimposed on some
H II regions.

Additional observations reported via IAU Circular 7690 include:  Aug. 15.76 UT,
<18.5: CCD, Garradd; 23.81 (prediscovery observation), 14.8 CCDV +/- 0.5, M.
Salvo and B. Schmidt (Australian National University - ANU), M. Ashley and A.
Phillips (University of New South Wales - UNSW), and C. Stubbs (University of
Washington), using UNSW Automated Patrol Telescope at Siding Spring; 25.65,
15.2 CCDV +/- 0.1, P. Francis (ANU), using Mt. Stromlo 1.9-m telescope; 26.47,
14.2 visual, A. Hale, Cloudcroft, NM.

Accompanying is an AAVSO Preliminary 'e' scale chart of NGC 1365 that shows
the location of SN 2001du, prepared by K. Malatesta, AAVSO Headquarters.
Please use this chart to observe the supernova and report your observations of
0329-36B SN 2001DU to AAVSO Headquarters, being sure to indicate which
comparison stars you used.

Congratulations to Bob on his latest visual discovery and his second in this
galaxy (his first being SN 1983V)!

2059+48  NOVA CYGNI 2001 NO. 2 = V2275 CYGNI

The Central Bureau for Telegrams (IAU Circular 7691) reports that N. Samus,
Institute of Astronomy, Moscow, Russia, announced that Nova Cygni 2001 No. 2
has been named V2275 Cygni.  Please report your observations of this nova as
2059+48 V2275 CYG.

Observations reported to the AAVSO indicate that V2275 Cyg has faded to visual
magnitude approximately 10.0 as of Aug. 27.3 UT.  The light curve of visual and
CCD observations and spectra received at the AAVSO through this date may be
seen on the AAVSO web page on V2275 Cyg at www.aavso.org/novacygni.stm (or go
to www.aavso.org and click on "N Cyg 01-2=V2275 Cyg update" under "Latest
News").

Accompanying is an AAVSO 'e' scale chart for V2275 Cyg, utilizing the sequence
chosen by Bruce Sumner from Arne Henden's photometry, prepared by G. Hawkins,
AAVSO Headquarters.  (Note that the 'ab' and 'b' scale charts issued with Alert
Notice 287 have had the name updated but are otherwise unchanged.)  Please use
these charts, and report your observations of 2059+48 V2275 CYG to AAVSO
Headquarters.

2003+17  WZ SAGITTAE SUPEROUTBURST UPDATE - DRAMATIC FLUCTUATIONS CONTINUE

WZ Sge is continuing in superoutburst.  Since it went into outburst on July 23
(see AAVSO Alert Notices 286 and 287), WZ Sge has been monitored extensively
by the amateur and professional astronomical community, with numerous satellite
or ground-based observing campaigns already carried out, underway, or scheduled
for the coming weeks.

Since reaching maximum visual magnitude of approximately 8.0 on July 23-24, WZ
Sge declined to magnitude approximately 10.7 by August 15.  The dramatic "dip"
of 2 magnitudes with fast recovery (see Alert Notice 287) began on August
16-17.  The star reached magnitude approximately 12.9 by August 18-19, by
August 21 recovered to visual magnitude approximately 10.7, and since then has
been fluctuating between magnitudes 10.7 and 12.7.

The latest composite light curve - updated every day - of observations
submitted to the AAVSO showing the current superoutburst and the 1978
superoutburst may be viewed on the WZ Sge page on our website (/wzsge.stm or
under Latest News).  Additional plots of CCD runs on the WZ Sge superhumps have
also been posted on this page; interested viewers are urged to check this page
frequently for additions.

As mentioned in AAVSO Alert Notice 287, observers are requested to continue to
monitor WZ Sge throughout the rest of this very rare superoutburst and
particularly after the star returns to minimum (in the 1978 superoutburst, it
took about 3 months after the dip for WZ Sge to return to minimum).  Both
visual and particularly CCD observers are urged to continue to monitor it for
superhumps by making observations every 3 to 5 minutes for several hours; be
sure to report the time to 4 decimal places of the Julian Date.  Extremely fast
CCD photometry (less than 1 minute exposure to exposure, preferably less than
30 seconds) in the last stages of the superoutburst and after return to minimum
has been urged by Dr. T. Marsh, University of Southampton, UK.  For details,
please see Alert Notice 287 and the full text of Dr. Marsh's communication on
our WZ Sge page.

Please use the 'b' and 'e' scale AAVSO Preliminary charts issued with Alert
Notice 286 to observe WZ Sge, and report your observations to AAVSO
Headquarters, making sure to indicate which comparison star(s) you used.

CHARTS AVAILABLE ON AAVSO WEB AND FTP SITES

Electronic copies of the charts for N Sgr 01-2, SN 2001du, V2275 Cyg, and
WZ Sge mentioned in this Alert Notice are available through our web site at
the following address:

                        http://www.aavso.org

The charts may also be obtained directly from our FTP site (209.192.236.2):

   ftp://ftp.aavso.org/alerts/alert288 (N Sgr 01-2, SN 2001du, V2275 Cyg)
                             /alert286 (WZ Sge)

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.

Many thanks for your valuable astronomical contributions and your efforts.

Good observing!

Janet A. Mattei
Director

Elizabeth O. Waagen
Senior Technical Assistant

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