Scientists observe flattest explosion ever seen in space

An explosion the size of our solar system has puzzled scientists, as part of its shape—like that of an extremely flat disk—defies everything we know about explosions in space. The observed explosion was a bright, fast blue optical transition (FBOT), an extremely rare class of explosion that occurs much less frequently than other explosions such as a supernova. The first shiny FBOT was discovered in 2018 and was nicknamed “nerd”.

Exploding stars in the universe are almost always spherical because the stars themselves are spherical. But this explosion, which occurred 180 million light-years away, is the most aspheric explosion ever seen in space, with a disc shape appearing days after its discovery. This part of the explosion may have been caused by matter the star ejected just before the explosion.

How bright the FBOT bursts are is still unclear, but this published observation has hope. Monthly Notices of the Royal Astronomical Societywill bring us closer to their understanding.

Dr Justin Maund, lead author of the study, from the Department of Physics and Astronomy at the University of Sheffield, said: “Very little is known about FBOT explosions – they do not act like exploding stars, they are very bright and evolve. They are, to put it simply, strange and this new observation makes them even more bizarre. doing.”

“Hopefully this new discovery helps us shed some more light on them – we never thought explosions could be so aspherical. There are several possible explanations for this: the stars involved may have formed a disk just before they died, or the core of the star turned into a black hole or neutron star and then bounced back.” There may be failed supernovae eating up the rest of the star.” .

“What we now know for sure is that the recorded asymmetry levels are an important part of understanding these mysterious explosions and are challenging our preconceptions about how stars might explode in the universe.”

The scientists made this discovery after they discovered a flash of polarized light entirely by accident. Using the Liverpool Telescope (owned by Liverpool John Moores University) in La Palma, they were able to measure the polarization of the explosion using the astronomical equivalent of Polaroid sunglasses.

By measuring the polarization, it allowed them to measure the shape of the explosion, effectively seeing something the size of our solar system but in a galaxy 180 million light-years away. They were then able to use the data to reconstruct the 3D shape of the blast and map the edges of the blast to see how flat it was.

The Liverpool telescope’s mirror is only 2.0 m in diameter, but astronomers studying polarization were able to reconstruct the shape of the explosion as if the telescope had a diameter of about 750 km. The researchers will now conduct a new study with the Vera Rubin International Observatory in Chile, which is expected to help discover more FBOTs and better understand them.