In the article “Black Hole Census Comes Up Way Short”, by Robert Roy Britthe explains how scientist tried to find an exact number of black holes that exist in our galaxy. The challenge is that black holes do not give of light so you cannot see them that is the challenge they face. The way they can detect them is to notice the light swells that surround them, or they detect the x-rays that are emitted. But that is the problem with stationary black holes they emit no x-rays, also they do not swell light do to the fact that they have already eaten all the surrounding stars that could possibly emit light. But when you look at something a far distance away you see into the past stages not the present this is explained, “ When scientists look across the universe, they're also looking back in time, so these more distant galaxies are also seen when they were much younger, in some cases while they were infants or teens in the growing universe.” (Britt 1)

I thought that this article was a little hard to grasp. They could have helped to explain the idea of the long distances of the universe and how you see the past and not present. Also the way that blackholes emit x-rays, needed to be explained.

Britt, Robert . "Black Hole Census Comes Up Way Short ." Space.com 26 July 2006: 1. Web. 19 May 2010.