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Special Notice #71: Next HST cataclysmic variable scheduled

October 11, 2007: The next HST object from Paula Szkody's program is scheduled to be observed during the week of October 29 through November 3. This is SDSS J074531.92+453829.5, another cataclysmic variable that is about V=19.1 at quiescence, and unknown brightness in outburst since it has never been observed to outburst. The coordinates are:

07:45:31.92 +45:38:29.5 J2000

and the AAVSO Harvard Designation and name is

0738+45 SDSS074545

We will send out another notice when the actual observation dates are fixed by the HST scheduling staff.

Dr. Szkody requests monitoring coverage of this object beginning now, and with intensive coverage for the 24hrs prior to the HST observation. The primary requirement, as for the PQ And campaign mentioned in Alert Notice 356: is that we need to show that SDSS074545 is faint enough to safely observe with the Hubble Space Telescope. Charts for this star can be generated using VSP, currently by inputting the coordinates (search by name will be added shortly). There are nice comparison stars near the CV; you may pick any one of these when reporting a fainter-than limit. A USNO-Flagstaff finding-image will be placed on the campaign webpage shortly.

Note that this object is a morning target, so we need geographical coverage to ensure that we can detect any beginning of an outburst.

This campaign is being organized at AAVSO HQ by Dr. Matthew Templeton.


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


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