The net of science covers the empirical universe: what is it made of (fact) and why does it work this way (theory). The net of religion extends over questions of moral meaning and value. These two magisteria do not overlap, nor do they encompass all inquiry (consider, for starters, the magisterium of art and the meaning of beauty). To cite the arch cliches, we get the age of rocks, and religion retains the rock of ages; we study how the heavens go, and they determine how to go to heaven.
But science and religion, as it is widely practiced, do overlap. They both make specific claims about the nature and history of the Universe. Some religionists do indeed make claims about the age of rocks.
Given the obvious overlap, it's not surprising that scientists--particularly those who work in the most fundamental and general of fields, like physics and cosmology--are often asked for their views on religion. In this short video from Big Think, astrophysicist and popular science writer Neil deGrasse Tyson explains why he is loathe to take sides on the issue, and why he dislikes the word "atheist."
"The moment when someone attaches you to a philosophy or a movement," says Tyson, "then they assign all the baggage, and all the rest of the philosophy that goes with it, to you. And when you want to have a conversation, they will assert that they already know everything important that there is to know about you because of that association. And that's not the way to have a conversation."