Astronomers: No chance of life on nearest planets

Life would not have a chance on planets nearest the Earth’s solar system because of a blizzard of comets and meteors, astronomers have concluded after taking a close look at the star Tau Ceti.

Tau Ceti, 12 light years away, probably has more than 10 times as many objects flying around as our own solar system does, scientists at the Royal Astronomical Society said.

“We don’t yet know whether there are any planets orbiting Tau Ceti, but if there are, it is likely that they will experience constant bombardment from asteroids of the kind that is believed to have wiped out the dinosaurs,” said Jane Greaves, lead scientist on the project.

“It is likely that with so many large impacts, life would not have the opportunity to evolve.”

The team made photographs of Tau Ceti with the highly sensitive SCUBA (submillimetre common-user bolometer array) camera operated on a telescope at the top of Mauna Kea in Hawaii.

The image shows a cloud of cold dust, minus 210C (minus 346F), surrounding the star. Scientists said the dust was produced by collisions between larger bodies.

“We will have to look for stars which are even more like the sun, in other words, ones which have only a small number of comets and asteroids,” Greaves said.

“It may be that hostile systems like Tau Ceti are just as common as suitable ones like the sun.”

Tau Ceti is in the constellation Cetus, but is hard to see at this time of year since it rises just before the sun.