The deadly comets that NASA says could one day hit Earth with devastating effects

Less than 50%

THERE are seven times more giant comets in the outer solar system - that could one day hit Earth - than was previously thought, scientists have warned.

The findings published in the Astronomical Journal, also found more comets than thought are leaving the Oort Cloud and passing the sun.

A Nasa spokesman said: "NASA's WISE spacecraft, scanning the entire sky at infrared wavelengths, has delivered new insights about these distant wanderers.

"Scientists found that there are about seven times more long-period comets measuring at least 0.6 miles (1km) across than had been predicted previously.

[link to www.express.co.uk (secure)]