‘Dwarf’ Offers Clues on Stellar Life Cycle

The discovery of new activity in a star thought to be a “white dwarf” stellar corpse may lend new insight into how stars are born, evolve and die, researchers said last week. When stars like the sun exhaust their fuel they become white dwarfs about the size of planet Earth. Astronomers have long believed that these objects are still cooling, incapable of further evolution.

The newly found star, known as 0950+139, is in the constellation Leo, about 1,500 light years from Earth, researchers told the American Astronomical Society. Scientists said the star is surrounded by a 50,000-year-old glowing cloud of gas about the size of Earth’s solar system and has shed additional gas long after entering the white dwarf stage.

“A spectrum like this, with unmistakable signs of a surrounding gas cloud has never been seen before in such a highly evolved star,” said Howard Bond, one of the researchers who presented the findings. “My co-workers and I believe the gas indicates that the star has very recently undergone additional mass loss.”