What does the X-ray Universe look like?
Only the hottest cosmological objects and the most energetic events generate X-rays. Studying them teaches astronomers about the violent Universe, where stars explode, black holes devour matter and galaxies collide.
The hottest objects and the most violent events in the Universe produce high-energy X-rays: solar flares, neutron stars, cosmic shock waves, extremely hot gas in galaxy clusters, colliding galaxies and matter spiralling into black holes. The human eye cannot see X-rays. In fact, your retina would be destroyed by this energetic cosmic radiation. Astronomers use representative colours to create images of the X-ray Universe, based on observations by Earth-orbiting space telescopes.
Our ears cannot hear the high pitch of a dog whistle. In the same way, our eyes cannot see X-rays coming from space. The pictures here show what you would see if you had X-ray vision.