Europe sets up asteroid detection centre
28 May 2013, 12:07
Rome - The European Space Agency (ESA) has set up an office to help provide early warnings when the Earth is about to be struck by natural objects such as asteroids.
The potential danger was starkly demonstrated in February by the explosion of a meteor above Russia's central Chelyabinsk region, shattering windows over a wide area and reportedly injuring some 1 200 people.
Called the NEO (Near-Earth Object) Co-ordination Centre, the new facility is part of ESA's European Space Research Institute (Esrin), located in Frascati, Italy, near Rome.
"It's of the utmost importance that asteroids be detected as early as possible so that their path can be ascertained," said Detlef Koschny, a planetary scientist and head of the NEO segment of ESA's Space Situational Awareness (SSA) Programme.
"What's now being brought together and combined in Frascati is the first step toward a European system."
According to Koschny, information will be pooled primarily from the Near-Earth Objects Dynamic Site (NEODyS) database operated by Space Dynamics Services S.r.l. at the University of Pisa along with data from other systems and sensors.
He said the Frascati centre would also serve as the focus point for scientific studies needed to improve NEO warning services and provide near real-time data to European and international customers.
Nearly 10 000 asteroids or comets are known to have orbits close to that of the Earth's.
They make up a fraction of all such objects in our solar system. Astronomers are aware of some 90% of the really large and dangerous near-Earth objects: One with a diameter of more than 1km would cause immense damage if it struck our planet.
"That's our rate with objects that are sufficiently large," Koschny said. "For smaller objects, with a diameter of 100m to 200m, we're not quite as good yet, unfortunately."
Only a small percentage of the smaller objects have been detected and therefore have calculable orbits, he noted, pointing out that the impact of even a "small" NEO, for example in the ocean, could trigger a devastating tsunami.
What action can be taken if a space threat is identified?
"If the asteroid is smaller than 100m in diameter, you run away, an evacuation is necessary," Koschny remarked. As for larger objects, he said it was important that they be detected a few years ahead of impact so that appropriate protective measures could be decided.
To deflect an asteroid on a collision course with Earth, a spacecraft could conceivably be launched to hit it.
Another theoretical possibility is use of what is known as a gravitational tractor, a massive spacecraft that hovers near the asteroid for years and gradually "tows" it off course with the help of thrusters and the bodies' mutual gravitational attraction.
"I'm confident we'll detect large asteroids years in advance - in time, that is," Koschny said.
A final possibility, he added, is blasting the oncoming asteroid off course with a nuclear explosion. While controversial, detonating an atomic bomb in space might someday be considered as the only way to save Earth from widespread destruction.