An explosion the size of our solar system has shocked scientists at the University of Sheffield, due to its unusually flat shape.

The explosion was an extremely rare Fast Blue Optical Transient (FBOT), a type of explosion that was first discovered in 2018 and given the nickname 'the cow'. To date, only four explosions of this class have ever been detected, and its causes are currently unknown. 

Explosions are almost always spherical, just like the stars themselves. However, a few days after its discovery, this particular explosion took the shape of a flat disk. It was observed 180 million lightyears away and it has been described as the "flattest" explosion ever detected. 

“Very little is known about FBOT explosions – they just don’t behave like exploding stars should, they are too bright and they evolve too quickly," said Dr Justyn Maund, lead author of the study. “Put simply, they are weird, and this new observation makes them...