Which of these stars would have the biggest redshift?
A) a star moving slowly toward you
B) a star moving fast toward you
C) a star moving slowly away from you
D) a star moving fast away from you
E) a star that is not moving away from you or toward you

Question

Quizplus · Accepted Answer

The Doppler effect causes the wavelength of light emitted by a moving source to appear stretched or shortened, depending on whether the source is moving away from or towards the observer, respectively. This shift is known as redshift or blueshift, respectively. The amount of redshift is directly proportional to the speed of the object relative to the observer, and inversely proportional to the wavelength of the emitted light. Therefore, a star moving fast away from the observer would have the largest redshift.

Which of These Stars Would Have the Biggest Redshift