13 billion light years! Astronomers have discovered the most distant quasar in the universe

Astronomers from the European Southern Observatory in Chile and the Max Planck Institute for Astronomy in Germany have discovered the oldest known source of radio emission, Live Science reports. It is a quasar located 13 billion light years from Earth.

Quasars are some of the oldest, most distant, most massive, and brightest objects in the universe. They represent the nuclei of galaxies in which a supermassive black hole absorbs matter caught in the field of its gravitational capture. Devouring this matter, the black hole emits powerful radiation that can be more than a trillion times brighter than the brightest stars. This makes quasars the brightest objects in the observable universe.

Quasars date back to the time when the first stars and galaxies were formed and the universe was still very young. The newly discovered quasar, named P172 + 18, has been dated to roughly 780 million years after the Big Bang. It belongs to one of the earliest eras - the era of reionization, which replaced the so-called Dark Ages, when the Universe was filled with hydrogen and helium. Then the first galaxies, stars and quasars appeared, they began to heat and ionize the surrounding gases, allowing light to pass through them.

Quasar P172 + 18 is nearly 300 million times more massive than the Sun and is one of the fastest growing quasars ever discovered. However, when astronomers compared their latest data with observations made more than two decades ago, they found that the quasar had lost half its brightness and probably reached the last stages of its life.

The results of the study will be published in the next issue of the Astrophysical Journal.