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[vsnet-campaign-news 53] AstroAlert: LMC V3804 remarkable brightening
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Remarkable Brightening of the Wolf-Rayet Star in the LMC
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Michael Mattiazzo (Wallaroo, South Australia) reports that the variable
star in the Large Magellanic Cloud (LMC), namely LMC V3804, has remarkably
brighter than usual. LMC V3804 is a Wolf-Rayet star, very massive star
whose hydrogen envelope had been blown off, and is considered to be an
immediate precursor to a supernova. Mattiazzo reports that LMC V3804
has attained a magnitude of 9.0 on 2001 April 28.60 UT. This brightening
makes LMC V3804 one of the few brightest stars in the LMC, even surpassing
some of novae discovered in the LMC. LMC V3804 is located in the region
of NGC 2070, a famous, bright diffuse nebula, and the region produced
a naked-eye supernova in 1987, SN 1987A. Fraser Farrell notes that
the field looked normal on March 30. No one knows whether the present
activity of LMC V3804 may lead to a more energic event, and further
observations are strongly recommended. Examination of photographs
in the near past may be useful in tracking back the activity of this
star.
LMC V3804 is located at 05h 38h 42.4s, -69o 06' 02" (J2000.0)
We have been undertaking on photometric campaigns on several super-
outbursting dwarf novae and peculiar variable stars like WR104. News and
call for observations on these objects will be issued on our regular weekly
"News from VSNET" bulletins. Those who immediately need information
should make an access to the VSNET website, and click on VSNET campaign list.
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VSNET (Variable Star Network) is an international variable star observing
network, covering various areas of novae, supernovae, cataclysmic variables
(CVs), X-ray transients, and other classical eruptive, pulsating, and
eclipsing variables. VSNET is one of invited contributing organizations
to the SkyPub AstroAlert system.
VSNET Home Page: http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/
CCD observations of such targets are a relatively easy task for a 20-40cm
telescope; simply take as many CCD frames (with exposure times 10-30 sec)
as possible, spanning several hours per night. The only requirements are
the weather and your patience! If you need more help on the observing
technique, please feel free to ask on the vsnet-campaign list.
We would sincerely appreciate volunteers who would join the VSNET
Collaboration team to study the wonders of these exotic variable stars.
To join the VSNET campaign collaborative list, send an e-mail to
vsnet-adm@kusastro.kyoto-u.ac.jp (VSNET administrator)
with a line "SUBSCRIBE vsnet-campaign." or your comment to join the
collaboration team.
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