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

Responses

temperature of the galaxy
temperature of the galaxy

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

The Big Bang theory
The Big Bang theory

composition of the universe
composition of the universe

motion of the galaxy
motion of the galaxy

expansion of the universe

1 answer

The shift of the hydrogen absorption spectrum of a galaxy primarily provides evidence for the following:

  1. Motion of the galaxy - The redshift or blueshift of spectral lines indicates whether the galaxy is moving away from or towards us.

  2. Expansion of the universe - The overall redshift of galaxies supports the idea that the universe is expanding, as observed by the increasing distance of more distant galaxies.

  3. The Big Bang theory - The redshift data is consistent with predictions made by the Big Bang theory, which explains the expansion of the universe from an initial singularity.

Therefore, the correct answers are:

  • motion of the galaxy
  • expansion of the universe
  • The Big Bang theory