You observe the spectrum of two stars.Star A has an emission line from a known element at 600 nm.Star B has emission lines from the same atom, but the emission line is occurring at 650 nm.One possible explanation for this observation is that star A is
A) cooler than star B.
B) farther away from us than star B.
C) moving toward us faster than star B.
D) made of different elements than star B.
E) larger than star B.

Question

Quizplus · Accepted Answer

The shift in the emission line from 600 nm to 650 nm for star B indicates a redshift, which suggests that star B is moving away from us. Therefore, star A is moving toward us faster than star B.

You Observe the Spectrum of Two Stars