BL Lac object


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Related to BL Lac object: abl, Blazar, Seyfert galaxy, ACBL

BL Lac object

n
(Celestial Objects) an extremely compact violently variable form of active galaxy
[C20: named after BL Lacertae, first identified example found in the constellation Lacerta and originally thought to be a variable star]
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References in periodicals archive ?
Pan, "Optical photometry of the BL Lac object 1ES1959+650," The Astronomical Journal, vol.
Finally, turning to his home soil of the Variable Star Section (VSS), the President congratulated Gary Poyner upon his fine observations of the BL Lac object OJ 287, made as a part of the VSS's observing campaign for the object.
Weekes notes that the gamma radiation generated by Markarian 421 probably comes from the edges of a jet believed to emanate from a quasar-like entity, called a BL Lac object, at the galaxy's center.
As a result of foreshortening and the proximity of the brilliant nucleus, any optical jet would be extremely difficult to detect in a BL Lac object. And, indeed, only one of the 40 or so BL Lacs studied in detail had ever been observed with such a feature.