Study: Dying sun will drive off comets

CAMBRIDGE, England, July 22 (UPI) -- When our sun ages and finally dies it will go out with a bang, throwing many of the solar system's comets into interstellar space, British scientists say.

In about 5 billion years it will run out of hydrogen to burn in its core and will expand to become a red giant star, eventually blowing off its atmosphere to leave an ember-like core called a white dwarf, NewScientist.com reported.

Researchers at the University of Cambridge say computer simulations show a sun's death throes will be felt as far as the vast cloud of comets in the so-called Ort cloud, well beyond the orbit of Pluto.

It's generally assumed the inner planets, including Earth, will be engulfed and incinerated during that phase, but now scientists say they believe the impact will be felt far beyond that.

As the sun loses mass, its gravity will decrease and that change can eject orbiting objects, and Dimitri Veras and his colleagues Cambridge said their simulations indicate as much as 20 percent of Ort cloud comets will fly away into interstellar space.