How do you calculate the radial velocity of a galaxy?

1 Answer
Write your answer here...
Start with a one sentence answer
Then teach the underlying concepts
Don't copy without citing sources
preview
?

Answer

Write a one sentence answer...

Answer:

Explanation

Explain in detail...

Explanation:

I want someone to double check my answer

Describe your changes (optional) 200

1
Peter Share
Mar 8, 2017

Answer:

Rotational speed is directly correlated to a galaxy's luminosity.

Explanation:

Rotation speed is a measure of a spiral galaxy's total mass. This is known as the "Tully-Fisher relation." Radiation from the galaxy where matter is generally approaching us is blueshifted by the Doppler effect. Radiation on the other side is redshifted by a similar amount. The overall effect is that line radiation from the galaxy is "smeared out" or broadened, by a galaxy's rotation. The faster the rotation the greater the amount of broadening.

Was this helpful? Let the contributor know!
1500
Trending questions
Impact of this question
234 views around the world
You can reuse this answer
Creative Commons License