Free Astronomy Magazine May-June 2021

36 MAY-JUNE 2021 ASTRO PUBLISHING around 780 million years old. While more distant quasars have been dis- covered, this is the first time as- tronomers have been able to identify the telltale signatures of radio jets in a quasar this early on in the history of the Universe. Only about 10% of quasars —which astronomers classify as “radio-loud” — have jets, which shine brightly at radio frequencies. P172+18 is powered by a black hole about 300 million times more mas- sive than our Sun that is consuming gas at a stunning rate. “The black hole is eating up matter very rapidly, growing in mass at one of the high- est rates ever observed,” explains as- tronomer Chiara Mazzucchelli, Fel- low at ESO in Chile, who led the dis- covery together with Eduardo Baña- dos of the Max Planck Institute for Astronomy in Germany. The astronomers think that there’s a link between the rapid growth of su- permassive black holes and the pow- erful radio jets spotted in quasars like P172+18. The jets are thought to be capable of disturbing the gas around Most distant quasar with powerful radio jets discovered W ith the help of the Euro- pean Southern Observa- tory’s Very Large Tele- scope (ESO’s VLT), astronomers have discovered and studied in detail the most distant source of radio emis- sion known to date. The source is a “radio-loud” quasar — a bright ob- ject with powerful jets emitting at radio wavelengths — that is so far away its light has taken 13 billion years to reach us. The discovery could provide impor- tant clues to help astronomers un- derstand the early Universe. Quasars are very bright objects that lie at the centre of some galaxies and are powered by supermassive black holes. As the black hole con- sumes the surrounding gas, energy is released, allowing astronomers to spot them even when they are very far away. The newly discovered quasar, nick- named P172+18, is so distant that light from it has travelled for about 13 billion years to reach us: we see it as it was when the Universe was just by ESO - Bárbara Ferreira