AGN host galaxies
type: Concept
broader: Active galaxies

Starburst galaxies
type: Concept
broader: Active galaxies

LINER galaxies
type: Concept
broader: Active galaxies

Haro galaxies
type: Concept
broader: Active galaxies

Blazars
type: Concept
broader: Active galaxies

BL Lacertae objects
type: Concept
broader: Active galaxies

Active galactic nuclei
type: Concept
broader: Active galaxies

Radio galaxies
type: Concept
broader: Active galaxies

Markarian galaxies
type: Concept
broader: Active galaxies

Active galaxies
type: Concept
narrower: LINER galaxies
narrower: AGN host galaxies
narrower: Blazars
narrower: BL Lacertae objects
narrower: Markarian galaxies
narrower: Radio galaxies
narrower: Haro galaxies
narrower: Active galactic nuclei
narrower: Starburst galaxies
broader: Galaxies
definition: A galaxy that produces huge amounts of energy at its center, which cannot be attributed to normal processes from stars, interstellar medium, and their interactions. There are several types of active galaxies: Seyfert galaxies, quasars, and blazars. All of these objects show brightness variations, some as short as 3 hours. These fluctuations indicate a relatively very small size for the central object, because an object cannot vary in brightness faster than light can travel across it. For example, an object that is one light-year in diameter cannot vary significantly in brightness over a period of less than one year.
contributor: AAS Frey.Katie
modified: 2020-11-03T17:54:46.169Z
modified: 2020-11-03T17:54:29.591Z

Galaxies
type: Concept
narrower: Active galaxies