Asked by Jaz

Question
Which does the shift of the hydrogen absorption spectrum of a galaxy provide evidence for? Select the three correct answers.(2 points)
Responses

motion of the galaxy
motion of the galaxy

number of stars in the galaxy
number of stars in the galaxy

temperature of the galaxy
temperature of the galaxy

expansion of the universe
expansion of the universe

composition of the universe
composition of the universe

The Big Bang theory
There are no human answers yet.
Answered by GPT-4o mini
The shift of the hydrogen absorption spectrum of a galaxy provides evidence for the following:

1. **Motion of the galaxy** - The Doppler effect causes a shift in the spectral lines of hydrogen due to the motion towards or away from us (redshift or blueshift).

2. **Expansion of the universe** - The overall redshift observed in light from distant galaxies indicates that the universe is expanding, a key observation that supports the Big Bang theory.

3. **Composition of the universe** - The specific absorption lines can be analyzed to determine the presence of hydrogen and other elements, giving insight into the composition of the universe.

Therefore, the three correct answers are:
1. Motion of the galaxy
2. Expansion of the universe
3. Composition of the universe