Archive for December 2007

Asteroid to hit Mars?

A newly discovered hunk of space rock has a one in 75 chance of slamming into the Red Planet on Jan. 30, scientists said Thursday.

“These odds are extremely unusual. We frequently work with really long odds when we track … threatening asteroids,” said Steve Chesley, an astronomer with the Near Earth Object Program at NASA’s Jet Propulsion Laboratory.

The asteroid, known as 2007 WD5, was discovered in late November and is similar in size to an object that hit remote central Siberia in 1908, unleashing energy equivalent to a 15-megaton nuclear bomb and wiping out 60 million trees.

Scientists tracking the asteroid, currently halfway between Earth and Mars, initially put the odds of impact at 1 in 350 but increased the chances this week. Scientists expect the odds to diminish again early next month after getting new observations of the asteroid’s orbit, Chesley said.

“We know that it’s going to fly by Mars and most likely going to miss, but there’s a possibility of an impact,” he said.

Full text: Discovery News : Discovery Channel

Baffling Cosmic Explosion Comes Out of Nowhere

A cosmic explosion that seems to have come out of nowhere—thousands of light-years from the nearest collection of stars—has left astronomers baffled.

The blast, one of the brightest this year, was detected by spacecraft from the Inter-Planetary Network on Jan. 25 and satellites were used to pinpoint its location to a region of the sky in the constellation Gemini.

Because the massive stars believed to produce GRBs live fast and die young, they don’t have time to wander from their birthplace, which is usually dense clouds of gas and dust inside of galaxies. So the explosion raise the perplexing question of how a massive star could be found so far from a galaxy.

“If a massive star died far away from any galaxy, the key question is, how did it manage to be born there?” said team member Derek Fox of Penn State. — Baffling Cosmic Explosion Comes Out of Nowhere