Groups of galaxies with large crossing times
Abstract
Virial masses of galaxies from the sample of Rood and Dickle (1978) drop at least a factor of 20 if the crossing times are greater than 10-billion. These groups appear to have virial masses equal to those expected if the motions of the member galaxies are caused only by the Hubble expansion. Therefore, a criterion for a group of galaxies to be bound appears to be a crossing-time less than 10-billion years, i.e., half the Hubble time.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- November 1980
- Bibcode:
- 1980A&A....91..365K
- Keywords:
-
- Galactic Rotation;
- Galactic Structure;
- Galaxies;
- Virial Theorem;
- Center Of Mass;
- Hubble Constant;
- Radial Velocity;
- Universal Time;
- Astrophysics