Chandra 101: Overview for Teachers and Students A Look at X-Rays

Why do we need X-ray telescopes?
Much of the matter in the universe cannot be seen by any other telescope. X-ray telescopes are the only way we can observe extremely hot matter with temperatures of millions of degrees Celsius. It takes gigantic explosions, or intense magnetic or gravitational fields to energize particles to these high temperatures. Where do such conditions exist? In an astonishing variety of places, ranging from the vast spaces between galaxies to the bizarre, collapsed worlds of neutron stars and black holes.

• More information: Comparing X-ray telescopes to doctor's x-rays