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AAVSO Alert Notice 411: Request for observations of the blazar 3C 66A AAVSO HOME > publications > alert notice

AAVSO Alert Notice 411

Request for observations of the blazar 3C 66A
October 31, 2009

Further to Alert Notice #353 (July 11, 2007), Dr. Markus Boettcher (Ohio
University) requests optical observations of the blazar 3C 66A during
its current high state.  Optical observations will support gamma-ray
observations by the VERITAS telescope in Arizona.  All observations,
including visual estimates and CCD photometry are encouraged.  3C 66A
has been brighter than average for several weeks, and is now above the
optical threshold of m(vis) ~ 14.1 for pursuing intensive optical
coverage.  Recent CCD and visual observations suggest a brightening
trend over past two weeks: JD 2455121.7698 (2009 Oct 17.2698),
m(V)=14.25 (E. Erdelyi, Carlsbad, CA, USA); 2455123.4201 (Oct 18.9201),
m(vis)=14.2 (K. Wenzel, Grossostheim, Ger.); 2455125.4375 (Oct 20.9375),
m(vis)=14.1 (Wenzel); 2455127.3750 (Oct 22.8750), m(vis)=14.0 (Wenzel);
2455129.6993 (Oct 25.1993), m(vis)=13.7 (M. Simonsen, Imlay City,
Michigan, USA); 2455135.3958 (Oct 30.8958), m(vis)=13.8 (Wenzel).

CCD observers are asked to obtain high S/N observations with filters if
possible; use an Rc if available for time series, and alternate with a B
or V filter if also available.  High signal to noise is preferred over
faster observing cadence.  One set of BVRcIc per night would also be
very useful.

3C 66A is located at the following (J2000) coordinates:

        RA: 02:22:39.61 , Dec: +43:02:07.8

Charts for 3C 66A may be plotted using AAVSO VSP:

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

For a description of the observing program, please see the text of
Alert Notice #353:

For more information on blazars and the AAVSO High Energy Network,
please visit

This AAVSO Alert Notice was prepared by Dr. Matthew Templeton.


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


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