Astronomy C

[Magikarpmaster629]

Questions (Click to Show Hidden Text)

1. What is an H II region?
2. What gives them their name?
3. Which of the DSOs on the list contain an H II region?
4. When we observe H II regions, what color do we see them as?

[Magikarpmaster629]

Is this dead?

[Adi1008]

Is this dead?

Not anymore

yolo (Click to Show Hidden Text)

1. a region of ionized hydrogen in space that when recombined with an electron, emits light at 656nm when the electron goes from n = 3 to n = 2 (called H alpha)
2. not sure, but is it because they contain ionized hydrogen, which is called H II?
3. M42
4. red (since they emit light at 656nm which is reddish light)

[Magikarpmaster629]

Is this dead?

Not anymore

yolo (Click to Show Hidden Text)

1. a region of ionized hydrogen in space that when recombined with an electron, emits light at 656nm when the electron goes from n = 3 to n = 2 (called H alpha)
2. not sure, but is it because they contain ionized hydrogen, which is called H II?
3. M42
4. red (since they emit light at 656nm which is reddish light)

yep

[Adi1008]

Is this dead?

Not anymore

yolo (Click to Show Hidden Text)

1. a region of ionized hydrogen in space that when recombined with an electron, emits light at 656nm when the electron goes from n = 3 to n = 2 (called H alpha)
2. not sure, but is it because they contain ionized hydrogen, which is called H II?
3. M42
4. red (since they emit light at 656nm which is reddish light)

yep

Do main sequence stars spin faster or slower than protostars of the same final mass? Why?

[finagle29]

Answer (Click to Show Hidden Text)

Main sequence stars spin slower than protostars of the same final mass; protostars have a greater radius and therefore greater rotational inertia so by the conservation of angular momentum as a protostar condenses further into a main sequence star it must spin faster.

[Magikarpmaster629]

Answer (Click to Show Hidden Text)

Main sequence stars spin slower than protostars of the same final mass; protostars have a greater radius and therefore greater rotational inertia so by the conservation of angular momentum as a protostar condenses further into a main sequence star it must spin faster.

Wouldn't a higher rotational inertia cause them to spin more slowly, given they are the same mass?

[finagle29]

Answer (Click to Show Hidden Text)

Main sequence stars spin [b][i][u]faster[/u][/i][/b] than protostars of the same final mass; protostars have a greater radius and therefore greater rotational inertia so by the conservation of angular momentum as a protostar condenses further into a main sequence star it must spin faster.

Wouldn't a higher rotational inertia cause them to spin more slowly, given they are the same mass?

You're right. I thought one think and typed the other.

[Adi1008]

Answer (Click to Show Hidden Text)

Main sequence stars spin [b][i][u]faster[/u][/i][/b] than protostars of the same final mass; protostars have a greater radius and therefore greater rotational inertia so by the conservation of angular momentum as a protostar condenses further into a main sequence star it must spin faster.

Wouldn't a higher rotational inertia cause them to spin more slowly, given they are the same mass?

You're right. I thought one think and typed the other.

Both of you are (now) right, y'all can choose who asks the next question

(sorry for the late response; I completely forgot about this)

[Magikarpmaster629]

I guess I'll go.

Explain the gravitational instability theory of gas giant formation, and some of its flaws.