| 释义 |
Definition of BL Lac object in English: BL Lac objectnoun Astronomy A type of remote elliptical galaxy with a very compact starlike nucleus, remarkable for its considerable short-term variations in brightness and radio emissions. Example sentencesExamples - Active elliptical galaxies are called BL Lac objects if their jets are viewed end-on; they look very different, having giant radio lobes, if their jets are viewed from the side.
- A number of BL Lac objects are known in the vicinity of clusters of galaxies so this provides indirect evidence in support of their extragalactic nature.
- However, BL Lac objects are the active cores of elliptical galaxies.
- The bright reddish object to the lower left of the center is a BL Lac object at the center of a cluster of galaxies.
- This result supports the interpretation of H2155 304 as a highly luminous BL Lac object.
Origin BL Lac, short for BL Lacertae, the designation of the first such object discovered (originally thought to be a variable star). Definition of BL Lac object in US English: BL Lac objectnoun Astronomy A type of remote elliptical galaxy with a very compact starlike nucleus, remarkable for its considerable short-term variations in brightness and radio emissions. Example sentencesExamples - The bright reddish object to the lower left of the center is a BL Lac object at the center of a cluster of galaxies.
- This result supports the interpretation of H2155 304 as a highly luminous BL Lac object.
- A number of BL Lac objects are known in the vicinity of clusters of galaxies so this provides indirect evidence in support of their extragalactic nature.
- However, BL Lac objects are the active cores of elliptical galaxies.
- Active elliptical galaxies are called BL Lac objects if their jets are viewed end-on; they look very different, having giant radio lobes, if their jets are viewed from the side.
Origin BL Lac, short for BL Lacertae, the designation of the first such object discovered (originally thought to be a variable star). |