Earth seems to have had a number of lucky escapes recent years; several asteroids have passed uncomfortably close to our home planet, and one exploded without warning in 2013 over Chelyabinsk in Russia, causing injuries to residents and extensive damage to buildings.
Now another piece of space debris has been identified as a potential risk, as scientists reveal that a mountain-sized asteroid could be on a collision course with planet Earth.
Russian scientist Vladimir Lipunov discovered the asteroid, using a network of robotic telescopes but has reassured the world’s media that it poses no immediate danger; however the huge asteroid, known as "2014 UR116", crosses our path every three years and there is a high risk of it colliding with Earth within the next 150 years.
Having advance warning is some comfort, as it is not always possible to detect asteroids before they enter our atmosphere – the Chelyabinsk meteor exploded without any prior warning – but 2014 UR116 could pack a mightier punch than its predecessor. If it collided with Earth, this incoming bolide could produce an explosion 1000 times larger than the Russian event, which itself caused damage for miles around the impact site.
How big a risk 2014 UR116 poses to Earth is still not known, as the trajectories of such large pieces of space rock can be constantly altered by the gravitational influences of other planets as they pass by. Lipunov warned that the progress of the meteor needed to be monitored closely as "even a small mistake in calculations could have serious consequences."
NASA was quick to squash any public concerns about 2014 UR116 saying that it currently did not pass close enough to the Earth to be considered a threat. It’s Near Earth Object Program Office said: "While this approximately 400-meter-sized asteroid has a three-year orbital period around the sun and returns to the Earth’s neighborhood periodically, it does not represent a threat because its orbital path does not pass sufficiently close to the Earth’s orbit."
NASA did admit that computer models indicated that the object should be considered to be a risk for the next 150 years, however, and that a collision could not be ruled out.
A recent gathering of international scientists examined the risk from asteroids and warned that there is the potential for such a collision to wipe out humanity unless more effort is made to track and destroy them. Asteroid monitoring is still an inexact science; it is easy to track some of the larger examples but smaller meteors can slip by undetected, a concern when one considers that even a rock measuring just 164 feet across could still cause significant damage if it crashed into Earth.
The Russians are already attempting to address this issue, and their space agency Roscosmos is working on a special detection system to be operational by 2025. They believe that the new technology could alter the trajectory of dangerous objects and divert them away from Earth. NASA has similar ongoing projects, Orbita@home and Spacewatch, and there are plans to deploy The Asteroid Terrestrial-impact Last Alert System (ATLAS) in 2015.
Lord Martin Rees, the Astronomer Royal, commented: “The ancients were correct in their belief that the heavens and the motion of astronomical bodies affect life on Earth – just not in the way they imagined.
“Sometimes those heavenly bodies run into Earth. This is why we must make it our mission to find asteroids before they find us.”