Bautz–Morgan classification
From Infogalactic: the planetary knowledge core
(Redirected from Bautz-Morgan classification)
The Bautz–Morgan classification was developed in 1970 by Laura P. Bautz and William Wilson Morgan to categorize galaxy clusters based on their morphology.[1] It defines three main types: I, II, and III. Intermediate types (I-II, II-III) are also allowed. A type IV was initially proposed, but later redacted before the final paper was published.[2]
Classificiation
- A type I cluster is dominated by a bright, large, supermassive cD galaxy; for example Abell 2029 and Abell 2199.
- A type II cluster contains elliptical galaxies whose brightness relative to the cluster is intermediate to that of type I and type III. The Coma Cluster is an example of a type II.
- A type III cluster has no remarkable members, such as the Virgo Cluster. Type-III has two subdivisions, type IIIE and type IIIS
- Type IIIE clusters do not contain many giant spirals
- Type IIIS clusters contain many giant spirals
- The deprecated type IV was for clusters whose brightest members were predominantly spirals.[2]
Examples
Example | Type | Notes | |
---|---|---|---|
100px | Abell 2199 | Type I | |
![]() |
Abell S740 | Type I-II | |
![]() |
Coma Cluster | Type II | |
100px | Abell 1689 | Type II-III | |
100px | Virgo Cluster | Type III | |
Type IIIS | |||
Type IIIE |
See also
- AGN classification
- Galaxy morphological classification
- List of Abell clusters
- Planetary classifications
- Stellar classification