Question

Which of these is the best method to estimate the speed at which a star is moving away from Earth?

measure the star's red shift
measure the star's blue shift
calculate the parallax due to changes in Earth's position
calculate the pitch due to changes in frequency of light

Answer 1

i think its red shift, the first one

Answer 2

here is a site with the same question: http://openstudy.com/study#/updates/4ee281e8e4b0a50f5c5642a6

Answer 3

hope this helped :)