Astronomers see death throes of giant star before violent explosion

Astronomers have long suspected that massive stars become red supergiants at the end of their lives, hiccup a few times and then explode in a classic supernova visible across the universe. But no one had ever seen this scenario play out in a single star.

Now, thanks to coordinated observations by numerous ground- and space-based telescopes, astronomers have recorded such a sequence for a star about 120 million light years from Earth and, before it collapsed and exploded, about 10 times the mass of the sun.