Martian bugs hitched a ride on meteorite

A meteorite which may contain evidence of Martian life stayed cool enough to allow the survival of bugs hitching a ride to Earth, scientists revealed yesterday.

A meteorite which may contain evidence of Martian life stayed cool enough to allow the survival of bugs hitching a ride to Earth, scientists revealed yesterday.

The discovery suggests that similar cool meteorites could, theoretically, carry micro-organisms between the planets.

The meteorite ALH84001 hit the headlines in 1996 when scientists at the United States space agency, Nasa, said it contained what looked like fossil microbes. Experts are still divided over whether the carbonate "blebs" are evidence of former life on Mars.

Like other Martian meteorites, ALH84001 was blasted off the planet's surface long ago by an asteroid or comet impact. After millions of years drifting in space, it was caught by the Earth's gravitational field to fall in the Antarctic.

The original impact would have generated high temperatures. But a new study of ALH84001 by US scientists shows that it was not heated above 40C. This is cool enough to have allowed bacteria or other bugs to survive unscathed.

The findings were reported today in the journal Science. The researchers, led by Benjamin Weiss, from the California Institute of Technology at Pasadena, wrote: "These data support the hypothesis that meteorites could transfer life between planets in the solar system."