Hubble watches a supernova light up again

n 1987, the light from an exploding star in a neighbouring galaxy, the Large Magellanic Cloud, reached Earth. Since its launch in 1990, the NASA/ESA Hubble Space Telescope has studied the wreckage of this dead star, called Supernova 1987A, and has watched it evolve. Supernova 1987A is the closest supernova to Earth to have been observed since the invention of the telescope, and is therefore an ideal laboratory for studying these phenomena.

A new study, published on 9 June in the journal Nature, sheds new light on one aspect of this supernova: for about fourteen years after the explosion was first seen, its afterglow gradually got dimmer as the radioactive elements produced by the supernova decayed. More recently, it has started to brighten once more, and is now two to three times brighter than it was at its dimmest point.

The team, led by Josefin Larsson of the University of Stockholm, has found that debris from the star’s explosion is impacting on a surrounding ring of gas, creating shock waves that produce X-rays, detected using NASA’s Chandra X-ray Observatory. These rays are, in turn, heating up the supernova debris and making it glow brightly once more.

The full story is explained in a press release on the website of the Harvard-Smithsonian Center for Astrophysics, the home institution of two of the study’s co-authors.

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http://www.spacetelescope.org/announcements/ann1111/

What's up with that cosmic omen? Beware of Republicon Chickenhawks? Good advice in any event.