For the first time, astronomers have obtained direct evidence that massive stars undergo supernova explosions and form black holes and neutron stars. The supernova event, named SN 2022jli, was discovered in May 2022 by South African amateur astronomer Berto Monard in the nearby galaxy NGC 157, 75 million light-years away. This discovery has brought to light a better understanding of the formation of dense celestial objects.
After analyzing the aftermath of the supernova explosion, two different teams from the Weizmann Institute of Science and Queen’s University Belfast used the Very Large Telescope (VLT) and the New Technology Telescope (NTT) to observe the event. The researchers were able to directly find evidence of the dense objects left behind by the explosion.
The behavior of the supernova event was also observed to be quite unusual. Instead of the gradual decrease in brightness typically seen in most supernovae, SN 2022jli exhibited oscillations every 12 days or so. The teams believe that this behavior is due to the presence of more than one star in the system, with one of the stars surviving the explosion of its companion.
Further analysis of the system’s hydrogen gas movements and gamma ray bursts led to the conclusion that the companion star was rich in hydrogen when it interacted with material thrown off during the supernova explosion. This interaction caused the atmosphere of the companion star to become fluffier than usual. The dense objects left behind by the explosion then began stealing hydrogen gas as they orbited the companion star, forming a hot material disk around themselves. This periodic material stealing behavior released a large amount of energy, causing the regular changes in observed brightness.
Although the researchers cannot directly observe light from the compact object itself, the energy accretion behavior indicates the presence of an invisible neutron star or black hole. The findings of these observations have been published in the journals “Nature” and “The Astrophysical Journal Letters.”
The direct evidence obtained from the SN 2022jli supernova event provides significant insight into the nature of dense celestial objects and the outcomes of supernova explosions. With further research, it is hoped that the exact nature of compact objects and the outcome of this system can be further unraveled. This breakthrough in our understanding of supernova events and the formation of black holes and neutron stars will undoubtedly pave the way for more discoveries in the future.