The Mystery of Dark Matter

We live in a big and mysterious place. I still haven't come to terms with the theory that most of the universe is made up of dark energy and dark matter, things that we cannot perceive directly. We can only see dark matter by its effects, such as ever-so-slightly bending beams of light.

This image shows the aftermath of a complicated collision of galaxy clusters, some of the most massive objects in the Universe. The colour red is used to show normal matter heated to millions of degrees, and blue shows the location of dark matter, detected by tracing the subtle light-bending effects on distant galaxies. The original photo is from the Chandra X-Ray Observatory. This photo is also shown, along with many other amazing ones, in the Top Ten Astronomy Pictures of 2007