Variable Stars

Anjum Mukadam, a former UT astrophysics grad student involved in the White dwarf project who is one of the colaborating scientists for this HST run, has asked CTAS to participate in this project using the PJMO and the Raptor Camera. If you have a 8" or larger telescope with CCD, or you are a visual observer with a really big light bucket telescope (15" or larger) you may be interested in trying your hand at "fainter than" observations using the faintest comparison star on the charts that you can see.

AAVSO Alert Notice 356
Request to monitor PQ Andromedae for HST Observations
August 24, 2007
Dr. Paula Szkody (University of Washington) has requested our help
in monitoring the nova PQ Andromedae for upcoming Hubble Space
Telescope observations. The HST observations are scheduled to be
made during the week of 2007 September 10-16 UT. Dr. Szkody requests
monitoring of this object during the two weeks prior to the
observing window, and intensive monitoring during the 24-48 hour
period during which observations will be made.
PQ Andromedae (0223+39) is at R.A. 02:29:29.61 , Dec +40:02:40.0
PQ Andromedae is the progenitor of Nova Andromedae 1988, and is
being observed as part of a larger study of pulsating white dwarf
primaries in cataclysmic variables. In particular, Szkody and
collaborators are investigating the effects that higher temperatures
and larger rotation velocities caused by accretion have on the
pulsation behavior.
This object is very faint at quiescence, with V=19.1, but reached
magnitude 12 during the 1988 outburst. AAVSO observations are
requested to ensure that the object is indeed faint when observed
with HST, as it could damage the instrument if it were to into
outburst. AAVSO observations will be used to make a "go"/"no go"
decision when the observing window opens, and will also be used in
the analysis of the resulting data.
Observers are asked to monitor PQ Andromedae nightly for the two
weeks beginning 2007 August 27 UT. Visual observers please observe
as normal, and report any "fainter than" estimates using the
faintest comparison star magnitude you can reach if unable to detect
PQ Andromedae itself. CCD observers are asked to use filters during
observations if available; V filter is preferred, but B,Rc, and Ic
may also be used. Detection of the variable itself is not required
unless you can reach V=19 in reasonable time, but please use
sufficient exposure to detect the V=14.5 comparison star (AUID
000-BBF-012; RA 02:29:41.98 Dec +40:04:20.7 ) northeast of the
variable. The preferred comparison star for a "fainter-than"
detection is the V=17.0 comparison (AUID 000-BBF-008; RA 02:29:34.67
Dec +40:04:40.9 ) north-northeast of the variable. If you can detect
PQ And, submit the comp stars used and the UT time of the
observation. There is a V=9.2 star within a few arcminutes southwest
of PQ And that will almost certainly saturate.
Beginning 2007 September 10 UT, please observe this object as often
as possible for the duration of the week using the observing
procedure outlined above, and submit data as soon as is possible via
WebObs. In the event of an outburst, please contact the AAVSO
immediately.
A charts for PQ Andromedae are available at this URL:
http://www.aavso.org/observing/charts/vsp/index.html?pickname=PQ%20And

For more information on this campaign, visit the following URL:
http://www.aavso.org/news/pqand.shtml
This campaign is being organized at AAVSO HQ by Dr. Matthew
Templeton.
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SUBMIT OBSERVATIONS TO THE AAVSO

Information on submitting observations to the AAVSO may be found at:

http://www.aavso.org/observing/submit/

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http://www.aavso.org/publications/alerts/