Brussels, 18 Jul 2003
New research carried out by scientists in Britain and Russia has concluded that the risk of a catastrophic large meteorite strike on Earth is much less than previously thought.
The study, carried out by Philip Bland of Imperial College London and Natalia Artemieva from the Institute for dynamics of geospheres in Moscow, downgrades the likely frequency of disastrous impacts by a factor of 50, relative to previous estimates.
According to the researchers, objects larger than 220 metres across are likely to hit the planet approximately every 170,000 years, compared with previous frequency estimates of 3,000 to 4,000 years.
However, it is not yet clear whether the new research significantly reduces the overall meteorite risk to Earth. Dr Bland and Dr Artemieva warn that impacts resulting from showers of fragments caused by previous collisions could have an equally devastating effect.
The level of risk posed by these galactic piles of rubble appears to depend on their makeup. Rocky asteroids, which account for about 93 per cent of all so called near-Earth objects, are more likely to break up completely in our atmosphere. The remainder, however, are mainly iron based and much more damaging if they hit the planet's surface.
While this most recent research offers some hope that we will avoid the fate that the dinosaurs suffered more than 60 million years ago, some, including the European Space Agency, are not leaving anything to chance, and are investigating ways to protect Earth from possible future impacts.