Scientists solve riddle of first supernova ever detected by man - 2,000 years ago

The riddle of the first documented star explosion has been solved - 2,000 years after the ancient supernova was spotted.

Chinese astronomers in 185 AD were the first to observe the mysterious 'guest star' that suddenly appeared in the sky and stayed for eight months.

But, it wasn't until the 1960s that scientists realised the object, named RCW 86, was actually the first documented example of a supernova - a star that has met a violent, explosive end.



Ancient mystery solved: This multi-wavelength view shows all that remains of the oldest documented example of supernova, RCW 86

They also found it to be a bigger-than-expected supernova remnant, 8,000 light years away. Each light year is about 6 trillion miles.

Just how the star's explosion had managed to travel so far has baffled scientists until now.

Pictures from Nasa's Spitzer Space Telescope and its Wide-field Infrared Survey Explorer (WISE) reveal the star exploded in a region of space relatively free of gas and dust.

Another view: The huge supernova is 8,000 light years away - each light year is about 6 trillion miles

This meant the explosion was able to travel much farther and faster, according to researchers.

'This supernova remnant got really big, really fast,' said Brian Williams, an astronomer at North Carolina State University in Raleigh, who carried out the study published in the Astrophysical Journal.

'It's two to three times bigger than we would expect for a supernova that was witnessed exploding nearly 2,000 years ago. Now, we've been able to finally pinpoint the cause.'

The star is a so-called Type Ia supernova triggered by the peaceful death of a star similar to our sun. The star first shrank into a dense white dwarf before sucking up material from another star, before exploding in a supernova.

