Astronomers have found a bit of cosmic history -- a star that obliterated its companion in a cataclysmic blast, famously lighting up the night four centuries ago.
In 1572, the Danish astronomer Tycho Brahe watched as an unknown "star" appeared, shattering the Aristotelian notion that the heavens never changed. It was so bright that it would have been visible even in the daytime. Young William Shakespeare, age 8 at the time, may have witnessed it and been inspired to include a celestial omen years later in Hamlet, some astronomers think.
But it wasn't a single star; it was two, orbiting so close together that gas from one was pouring onto the other. When the second one got heavy enough, it blew up. That cataclysmic explosion, called a supernova, is what Tycho witnessed.
Pilar Ruiz-Lapuente, an astronomer at the University of Barcelona, and her colleagues now have identified the original star that triggered the blast. It's an ordinary star like the sun, about 10,000 light-years from Earth, in just the right place to have set off the supernova.
The discovery could help explain exactly how this type of supernova begins, the scientists wrote in Nature.
-- Dallas Morning News