While examining the spectrum of a galaxy, you find all the hydrogen lines are shifted to longer wavelengths. This galaxy is
A) moving away from us.
B) moving towards us.
C) blueshifted.
D) expanding explosively.
E) not forming new stars.

Question

Quizplus · Accepted Answer

The shift of hydrogen lines to longer wavelengths in the spectrum of a galaxy indicates a redshift, which means the galaxy is moving away from us.

While Examining the Spectrum of a Galaxy, You Find All