The basic picture is probably correct. I will now discuss some
details of the star formation problem. I will make extensive use the
Hertzsprung-Russell diagram (as a tool in the discussion).
We have already talked about the basics of star formation. The fundamental
To make the ideas concrete, I will talk about the formation of stars of mass,
say, less than around 2 x the mass of the Sun. Such protostars are
referred to as T Tauri stars. Note, however, that the basic ideas are the
same for all protostars. It turns out that it is primarily how
protostars appear and where they form in the clouds (and therefore
presumably how they are triggered) which differs according to their masses.
The preceding are telling us
many things, most of which we don't understand.
- T Tauri
stars may form in smaller Giant Molecular Clouds (not well-established)
where T less than ~ 10 K, e.g., Taurus Complex; also may form
throughout such clouds
Protostars appear to form in the larger Giant Molecular Clouds where T
greater than 20 K, e. g., Orion; appear to form at
the edges of the clouds (more secure)