Supernova caught exploding on camera

WASHINGTON (Reuters) - Excited astronomers said on Wednesday they had for the first time caught a supernova on camera just as it was exploding, and they may now learn how to spot others.

By luck, they spotted a burst of X-rays while looking at another part of a distant galaxy, and managed to turn a variety of telescopes in the right direction just in time.

"For years, we have dreamed of seeing a star just as it was exploding," said Alicia Soderberg of Princeton University in New Jersey, who led the international team of astronomers.

"We were in the right place, at the right time, with the right telescope, on January 9th and witnessed history," she added in a statement.

A supernova is a dying star, but one much bigger than Earth's sun. It first explodes outwards, then shrinks into itself to form an extremely dense, cold ball. Sometimes a neutron star results and sometimes a black hole.

Soderberg's team looked across space and time to witness the death throes of supernova 2008D, found in one arm of the galaxy NGC 2770, 88 million light-years from Earth.

In real time, they are seeing events that occurred 88 million years ago -- but in Earth time they are just occurring and the astronomers can watch the supernova as if it really were exploding just now.

"Using the most powerful radio, optical and X-ray telescopes on the ground and in space we were able to observe the evolution of the explosion right from the start," said Edo Berger, who like Soderberg is a Carnegie-Princeton fellow.

"This eventually confirmed that the big X-ray blast marked the birth of a supernova."