The spectra of most galaxies tell us that:
A) most galaxies appear to be moving away from us
B) their light comes predominantly from objects other than stars
C) most galaxies contain clouds of gas that are absorbing their favorite wavelengths
D) galaxies in the past rotated at a faster rate than they do today
E) galaxies are rushing through space at high speeds

Question

Quizplus · Accepted Answer

Most galaxies appear to be moving away from us as indicated by the redshift in their spectra, which is a result of the Doppler effect. This is known as Hubble's Law, which states that the further a galaxy is from us, the faster it appears to be moving away from us.

The Spectra of Most Galaxies Tell Us That