Astr 202 March 27, 2001

Galaxy classification

Reading:
Fraknoi 25.1 - 25.3 and 24.4

The Hubble tuning fork diagram
Elliptical galaxies
Spiral galaxies
Irregular galaxies
Peculiar galaxies
Galactic Collisions
Hubble Deep Field
Low surface brightness galaxies
Classify the galaxies in the Hubble Deep Field

Normal galaxies -- the Hubble sequence and additions such as low surface brightnes galaxies; dark matter in galaxies

Classifying galaxies -- the Hubble sequence
Elliptical galaxies

M87, bright elliptical in Virgo cluster
the Leo I dwarf spheroidal galaxy

Spiral galaxies

Local Group galaxy M33 (Sc)
NGC 891 -- the Milky Way's "twin"? (Sb)
NGC 253
NGC 1365 SB
NGC 4594, the Sombrero galaxy (Sa)

Less obvious galaxies
Irregular galaxies

The Large Magellanic Cloud
The Small Magellanic Cloud
NGC 6822, Local Group Irregular galaxy

M101, prototypical high surface brightness spiral
Malin I, large low surface brightness disk galaxy

Hubble deep field wide view
Hubble deep field details