When massive stars die, they explode as supernovae. The light from these events is very bright and can be seen from millions and even billions of light-years away. Now, astronomers have discovered the farthest explosion of a massive star, reports Focus.
Scientists using the Webb Space Telescope have discovered the farthest, and thus the oldest, supernova known. Massive stars explode as supernovae and turn into neutron stars or black holes when they run out of hydrogen fuel for nuclear fusion that sustains their life. Prior to this discovery, the oldest supernova was one that occurred 1.8 billion years after the Big Bang. Now, astronomers have found a new record-holder – a supernova that exploded 730 million years after the Big Bang, which marked the beginning of the universe 13.8 billion years ago. The study is published in the journal Astronomy & Astrophysics, reports Space.
Initially, astronomers discovered a powerful gamma-ray burst, which is gamma radiation coming from very deep space, using space observatories. This gamma-ray burst was named GRB 250314A. Such gamma-ray emissions occur during a supernova explosion and indicate that a massive star has collapsed and turned into a black hole.
Calculations by astronomers showed that the gamma radiation traveled to us for 13 billion years. Scientists hypothesized that the gamma-ray burst was related to the supernova explosion, and with the help of the Webb Space Telescope, they were able to detect it.
According to the authors of the study, this is the farthest and oldest supernova known. The previous oldest explosion of a massive star occurred 1.8 billion years after the Big Bang, meaning it is 12 billion years old. However, the discovered supernova originated 13 billion years ago.
Interestingly, astronomers had previously detected only a few gamma-ray bursts that occurred during the first billion years of the universe's existence. The Webb Space Telescope was also able to identify the galaxy in which the supernova explosion occurred and learned something about the galactic environment of this ancient star explosion.
Astronomers found that the very distant galaxy resembles other galaxies that existed at the same time. The light spectrum of the supernova also looks remarkably similar to the light spectrum of modern supernova explosions. Scientists also concluded that the mass of the exploded star is not anomalous and resembles the mass of modern massive stars.
Still, astronomers believe that further observations may reveal some differences, considering that the supernova exploded during a period in the universe's history when there were significantly fewer heavy chemical elements present. That is, elements heavier than hydrogen and helium.
In any case, the discovered supernova is currently the record-holder among similar events known to astronomers.
Leave a comment