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Special Notice #296: Outburst of the BL Lac object 4C 11.69 == CTA 102

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October 6, 2012:  The BL Lac object 4C 11.69 (== CTA 102) was discovered in bright outburst by V. Larionov, D. Blinov, and S. Jorstad (St. Petersburg University and Boston University) on 2012 September 18, reaching a magnitude of R=14.67; see ATel #4397 (  Those authors also claim a coincident substantial increase in the gamma ray flux as observed by the Fermi LAT instrument.  As of 2012 September 19.8799, they found the source was still brighter than R=15.1 but fading rapidly.   Observations of this interesting source are encouraged over the next several days.  The object has been around m(vis) = 16.5 for the past few hundred days; the most recent AAVSO observation was m(vis)=16.4 on 2012 August 17.005 (JD 2456156.505) by Adolfo Darriba Martinez (Spain).

4C 11.69 is located at the following J2000 coordinates:

RA: 22 32 36.41 , Dec: +11 43 50.9

A new sequence expanding upon previously released comparisons from the GTN project has been prepared by Tim Crawford of the AAVSO Sequence team and is available via VSP:

Please use the name "4C 11.69" when submitting observations to the AAVSO.

This AAVSO Special Notice was prepared by M. Templeton.

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