A star is observed moving away from Earth. What can you conclude about the spectrum of that star?

The spectrum will shift to the blue.

The spectrum will shift to the red.

The spectrum will not change.

The spectrum will shift first to the blue, and then to the red.

Question

A star is observed moving away from Earth. What can you conclude about the spectrum of that star?

 The spectrum will shift to the blue.

 The spectrum will shift to the red.

 The spectrum will not change.

 The spectrum will shift first to the blue, and then to the red.

shane_b · Answer

Redshift...which is what happens when light is coming from a distant object that is moving away and the wavelengths become longer.  Blue-shift is the opposite of red-shift.