Now you see them, now you don’t. Scientists have discovered that some of the most powerful explosions in the universe, hypernovae, may not occur at all. These explosions, known as hypernovae, were first proposed to explain unusual stars in the halo of our Milky Way galaxy and a neighboring dwarf galaxy. It was suggested that these stars could only form from the remains of an explosion 10 times more powerful than the “average” supernovae. The team behind these new findings suggests that ordinary supernovae could actually explain these stars when you consider the uneven or non-spherical way they spew matter. not their overall combination of elements,” team leader Anmol Aggarwal of University College London (UCL) said in a statement. “We developed mathematical models that took this into account and found in all cases that stars with a very unusual mix of ingredients probably formed from ordinary supernovae. “All the evidence we see for hypernovae suddenly disappears.” You may like Hypernova versus supernova: What’s the difference? Supernovae occur when massive stars run out of fuel for nuclear fusion, effectively ending their lives. This results in the collapse of the star’s core, sending shock waves that spread through its outer layers, causing explosions we call supernovae. Hypernovae are proposed to occur in a similar way, but for an even more massive and rapidly spinning star. This results in a much more energetic explosion. When supernovae or hypernovae occur, they spew elements that the dying star has forged throughout its life into the surrounding cosmic environments. These elements eventually become the building blocks of the next generation of stars. That means analyzing the chemical signatures of stars can inform stellar scientists about artists’ impression of a hypernova. gamma-ray jets (Image credit: NASA/JPL-CALTECH) “Just before a star goes supernova, it has layers like an onion, with heavier elements in the center and lighter ones further out. Our model looks at how much material from each layer or each region would be needed to fit the observed star,” said Ralph Schoenrich from UCL’s Mullard Space Sciences Laboratory. “We still don’t know how well supernova material mixes before forming new stars. This is despite decades of work in this area. Our research suggests that some mixing occurs, but incompletely. What to read next “We need to take this into account in our models of how chemicals evolve in galaxies and how the interstellar medium works.” The team began their research by looking at four stars suspected to have been forged from material ejected in a hypernova explosion. The team concluded that it was more three of those stars were likely created after supernovae. Artist’s impression of dust surrounding a red giant star (Image credit: Anna Mayall) Scientists then studied a single red giant star in the Milky Way’s halo with a strange chemical composition, including an overabundance of heavy elements such as silver and uranium. These are too heavy to be forged in the cores of all but the most massive stars, the type of stars that become. hypernovae. These elements could also be created when two massive, dense stellar remnants called neutron stars collide and merge. However, this star has no other heavy elements that would be present after a neutron star collision. This team considered the origins of this star using a model of the Milky Way that has been rapidly enriched with elements heavier than hydrogen and helium, which astronomers call metals, through the death of the first generation of stars and. The event that created it, they concluded, was the combination of a neutron star merger and an ordinary supernova. The scientists found that an asymmetric supernova would be enough. The team’s research was published in two papers in the journal Monthly Notices of the Royal Astronomical Society.
