In 2009, a giant star 25 times more massive than the Sun disappeared. We tell you what happened to him. Astronomers have observed an object in space that has undergone a period of intense expansion, reaching the size of a million Suns. In theory, the star N6946-BH1 is approaching a supernova explosion. However, the expected explosion did not occur and the object disappeared instead of becoming a supernova. Using the Large Binocular Telescope (LBT), Hubble Space Telescope, and Spitzer Space Telescope, astronomers were unable to determine the star’s fate. The star is considered a failed supernova. Astronomers believe that this object collapsed into a black hole and did not cause a supernova explosion.
Scientists know that it gets bright for a while, then becomes too dark to see with a telescope. But that’s changed thanks to the James Webb Space Telescope (JWST).
A recent study published in the journal arXiv used data obtained from JWST’s NIRCam and MIRI instruments. In one of the images, scientists see a bright infrared source that looks like the remains of the dusty shell that surrounded the original star. This may be the result of material being ejected from the star as it rapidly becomes brighter. It’s also possible that it’s infrared radiation from matter falling into the black hole, although this scenario is less likely. An interesting fact is that researchers were able to discover not one, but three remaining parts of this object. This makes the idea of a failed supernova less likely.
A more likely pattern is that the 2009 shine was caused by a particular merger. What appears to be a bright, massive star is actually a star system that grows brighter as the two stars merge and then dim.
Stellar-mass black holes exist and form quite frequently from very massive stars. However, the question remains whether black holes can be the result of a supernova explosion. Supernovae often have enough mass left over to become black holes, but it’s hard to imagine how the largest stellar black holes could form after a supernova. Black hole formation requires massive stars. During a supernova explosion, energy is released from the star, which can prevent black hole formation, as this process involves conservation of mass in a compact object.
One theory is that a supernova could form a neutron star, which would then collapse further, forming a black hole. N6946-BH1 is located 22 million light years from Earth. With more data, scientists will be able to distinguish between stellar mergers and true failed supernovae. This will help understand the final stages of the life cycle of cosmic objects, when they transform into stellar-mass black holes.
Scientists have followed the evolution of SN 1987A as it went from a flash of light first observed in February 1987 to a fully formed supernova remnant. This object is located just 168,000 light years away from us. New observations have revealed never-before-seen structures in a growing cloud of exploding stellar “internals.”
source: https://arxiv.org/abs/2309.16121