Quasar luminosities can vary considerably over time, depending on their surroundings. Since it is difficult to fuel quasars for many billions of years, after a quasar finishes accreting the surrounding gas and …

Jun 3, 2025 · Quasars occur when immense amounts of matter fall into a supermassive black hole, spiraling around it in the form of a disk before entering.

Dec 10, 2025 · Quasar, an astronomical object of very high luminosity found in the centres of some galaxies and powered by gas spiraling at high velocity into an extremely large black hole.

Quasars are a subclass of active galactic nuclei (AGNs), extremely luminous galactic cores where gas and dust falling into a supermassive black hole emit electromagnetic radiation across the entire …

Oct 29, 2024 · Learn what a quasar is in astronomy, how it forms, types of quasars, and what they tell us about the early universe.

Dec 11, 2025 · Astronomers challenge 50-year-old quasar law by Sam Tonkin, Royal Astronomical Society edited by Lisa Lock, reviewed by Robert Egan Editors' notes

Apr 14, 2025 · A quasar is an extremely bright galactic core powered by a supermassive black hole, emitting massive energy as gas spirals inward, outshining entire galaxies.