AAVSO Alert Notice 356: Request to monitor PQ Andromedae for HST Observations

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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