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Special Notice #194: Request for monitoring of the blazar 3C 66A

February 9, 2010: The blazar 3C 66A has been steadily brightening in the optical for the past few hundred days, and is now at or near the bright limits of the AAVSO records for this object. The most recent observations put 3C 66A near V=13.9: m(vis)=13.8, JD 2455234.361 (2010 Feb 06.861; G. Poyner, Birmingham, England); m(V)=13.88, JD 2455235.566 (Feb 08.066; R. Campbell, Largo, Florida, USA); m(V)=13.90, JD 2455235.740 (Feb 08.240; R. Campbell).

Observations of 3C 66A are encouraged to track the current activity cycle. All observations including visual, single-filter CCD, and multi-filter CCD photometry are encouraged. The majority of AAVSO instrumental photometry is in the V-band, but all photometric filters are useful for this object. Intensive time-series observations are not required, but hourly or nightly monitoring will be very useful. Please obtain S/N of at least 50 when performing photometry.

Observers should note that the 136 comparison star (AUID 000-BBD-768) has been reported as variable and should be avoided if possible. Also note that the comparison magnitudes are based upon a single night of photometry; please retain and report the IDs of all comparison stars used so that photometry can be adjusted if the sequence is revised. Observers should also note that 3C 66A lies in a galaxy-rich field, and the use of DSS-based VSP charts is recommended when identification of the object is in question.

The blazar 3C 66A is located at the following (J2000) coordinates: RA: 02:22:39.612 , Dec: +43:02:07.80

Charts for 3C 66A may be plotted using the AAVSO Variable Star Plotter:

Please submit observations to the AAVSO using the name "3C 66A".

This AAVSO Special Notice was prepared by M. Templeton.


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