|MLA Citation:||Bloomfield, Louis A. "Question 914"|
How Everything Works 21 Jan 2018. 21 Jan 2018 <http://howeverythingworks.org/print1.php?QNum=914>.
Quasars exhibit enormous red shifts and one explanation for those red shifts is that the quasars are located near the other side of the universe. If so, they would be moving away from us rapidly, along with their surroundings in the expanding universe, and their light would appear highly red shifted. Moreover, their light would have been traveling almost since the beginning of the universe so that we would be observing very ancient objects. However, it's also possible that quasars are much near to us and that their red shifts are caused by gravitational effects rather than relative motion. As far as I know, this possibility can't be ruled out and remains a concern amount the astronomical community.