Observing Campaign to Monitor AR UMa
for Spitzer Space Telescope Observations

Spitzer Space Telescope (Courtesy: NASA)

From AAVSO Alert Notice 348:

Dr. Steve Howell (National Optical Astronomy Observatory) and Dr. Donald Hoard (Spitzer Science Center) have requested time-series observations of the AM Herculis-type cataclysmic variable AR UMa (11:15:44.68 +42:58:22.5 (J2000)) to coincide with upcoming Spitzer Space Telescope observations.

Both B- and V-band CCD time-series observations are requested leading up to and during the Spitzer observations scheduled for 2007 May 9-10, and continuing through May 13-14. Time-series observations during the May 9-10 observing window are most critically needed, while time-series observations before and after will help to establish the range of behavior of this object. The star varies between V=14.5 and V=16.5; please use exposure times that yield a signal-to-noise ratio of 50 per measurement.

Charts: AR UMa charts and Henden sequence file

Observing Window:

Intensive Observing Window:

Both visual and CCD observations are useful, but V-band time-series observations are most urgently requested. Please use exposure times such that you can obtain a signal-to-noise of 50 per observation.

Light Curves

Light curve as of 070502: