A Quasar is an energetic object in space that looks like a star. They are actually galaxies, very far away, with very bright cores in the middle. They are probably the brightest objects in the whole Universe. Many times brighter than normal galaxies. A quasar can be as bright as 1,000 Milky Way galaxies!
Astronomers think that quasars are powered by supermassive black holes found at the centre of most galaxies. The power from a quasar comes from material crashing together at enormous speeds. This is because the material is being pulled into the black hole and swirling around.
The material comes from stars which have got too close to the black hole. The gravity from the black hole is so strong that it pulls the stars apart. This makes a string of huge explosions that can be seen across the Universe. The furthest quasar we can see is more than 13 billion light years away!