WR124
An example of a relatively close-by Wolf Rayet star, in this case obtained with the Hubble Space Telescope. Image: Hubble Legacy Archive, NASA, ESA - Processing & Licence: Judy Schmidt (creative commons)

 

The astronomers - including scientists at the Department of Astronomy, Stockholm University - interpret the stellar explosions as the outcome of a very massive star, probably more than 25 times heavier than our Sun, that before the explosion lost a large fraction of its mass in strong stellar winds.

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