Astronomers have established a direct connection between the explosive demise of massive stars and the creation of black holes and neutron stars, the most condensed and enigmatic entities in the universe.
Two research teams closely examined the immediate aftermath of a supernova explosion within a nearby galaxy, uncovering evidence for the enigmatic compact object left in its wake. Utilizing data from The European Southern Observatory’s Very Large Telescope (VLT) and ESO’s New Technology Telescope (NTT), these observations shed light on the mysterious remnants.
When stars significantly more massive than our sun conclude their life cycles, their gravitational collapse triggers a rapid and violent explosion known as a supernova. Astronomers posit that following the explosion, only the ultra-dense core, or “compact remnant,” of the star persists. Depending on the star’s initial mass, this remnant evolves into either a neutron star or a black hole.
A neutron star is an exceptionally dense object, with a teaspoon of its material weighing approximately a trillion kilograms on Earth. Meanwhile, a black hole boasts even greater density, possessing gravity so intense that nothing, not even light, can escape.
While the compact remnant theory aligns with numerous clues regarding the sequence of events during a star’s explosion, direct evidence of a supernova leaving behind such a remnant has eluded astronomers until recently. In 2022, South African amateur astronomer Berto Monard discovered supernova SN 2022jli in the spiral arm of the nearby galaxy NGC 157, situated approximately 75 million light-years away. Examining its aftermath, researchers noted peculiar behavior.
Unlike most supernovae, whose brightness gradually diminishes over time, SN 2022jli displayed a distinctive pattern. While overall brightness decreased, it oscillated in an up-and-down cycle roughly every 12 days.
Upon analyzing all the evidence, researchers concluded that this unusual pattern is the result of a compact remnant interacting with the supernova’s companion star, which managed to survive the explosion.
