Researchers have discovered lot of asteroids and comets floating near our planet in space in past two decades that has increased the risk of these comets colliding with our Earth which will have a catastrophic effect, warns new study.
Study authors are worried for giant comments called centaurs — nearly 50 to 100 kilometers in diameters and a single such body contains more mass than the entire population of Earth-crossing asteroids found to date. Path of these centaurs crosses orbits of outer planets including Jupiter, Saturn, Uranus and Neptune. Since, centaurs move in unstable orbits, gravitational fields of large outer planets can deflect centaurs towards Earth, say astronomers from the Armagh Observatory and the Univeristy of Buckingham in UK.
After analysing the path of centaurs, study authors came to a conclusion that at least one giant comet will collide with Earth in every 40,000 to 100,000 years. However, large part of those centaurs moving towards earth will disintegrate into dust and smaller fragments due to near-Earth space. According to researchers, after breaking up into several pieces, those centaurs will flood the inner solar system with cometary debris and making impacts on our planet inevitable.
“In the last three decades we have invested a lot of effort in tracking and analysing the risk of a collision between Earth and an asteroid,” said Professor Bill Napier from the University of Buckingham. “Our work suggests we need to look beyond our immediate neighbourhood too, and look out beyond the orbit of Jupiter to find centaurs. If we are right, then these distant comets could be a serious hazard, and it’s time to understand them better,” said Napier.
The findings are consistent with the history and our understanding of cometary population.
The study appeared in the journal Astronomy and Geophysics.