New novas live fast, die young

Stephen Withers
Thursday, 10 May 2007 04:43

Science - Space

Astronomers using the ESA's XMM-Newton and NASA's Chandra orbiting X-ray observatories have found a new class of exploding stars, or novas, that burn very quickly.

While watching the Andromeda galaxy, a team from the Max Planck Institut für Extraterrestrische Physik discovered that X-ray emissions from some novas start and stop within a few months where others last at least a decade.

The X-ray emissions follow the visible explosion occurring when a white dwarf star nears the end of its life.

"These novae are a new class. They would have been overlooked before," said  Wolfgang Pietsch of the Planck Institut. Previous surveys only examined regions about twice a year, giving time for fast X-ray novas to come and go without being seen.

The fastest changing novas are thought to be associated with the most massive white dwarfs.

Pietsch's team have been allocated additional XMM-Newton and Chandra time, and plan to observe novas in Andromeda at ten-day intervals for several months beginning in November.