Nasa Probe To Visit Danger Asteroid

NASA is to fly a mission to an asteroid that threatens Earth with an Armageddon-style impact. The $800million probe, called Osiris-Rex, will launch in 2016 but it will not be manned. 

Osiris-Rex plucks sample from the asteroid (NASA/Goddard/University of Arizona)

Its target will be a space rock that will be headed straight for us in 2182. Months will be spent mapping the asteroid, dubbed 1999 RQ36 and more than a third of a mile wide, after the probe reaches it in 2020.

A robotic will pluck material from its surface and send it flying back in a secure capsule to land in Utah in 2023. This is the same technique that was used in 2006 to retrieve a cannister of dust from a comet encounter in the Stardust mission. The asteroid, a member of the Apollo group, is thought to have changed little since the birth of the solar system. NASA scientists will study its organic chemistry for clues as to how life began.

It takes around 14 months to go round the Sun. However, a disturbance called the Yarkovsky effect, caused by the force of sunlight on smaller rocks, introduces a significant “orbital uncertainty”.

By studying the effects of sunlight on this asteroid’s orbit, NASA hopes also to learn how best to deflect such cosmic misiles so that they do not hit the Earth.

But unlike the hit movie with Bruce Willis, the spaceacraft will simply fly around it for six months and send back a tiny sample from its surface.

Using nuclear missiles to blow up an asteroid, as in the Armageddon movie, is not considered a real option because you just end up with more rocky fragments to worry about.

Scientists from Spain, Italy and NASA’s Jet Propulsion Laboratory in California have previously predicted that there is a one-in-a-thousand chance of 1999 RQ36 striking the Earth some time in the future, with 2182 being a key date with a higher level of danger.

Another giant asteroid will come within the orbit of the Moon in November this year, though there is no danger of an impact. And yet another, called Apophis, continues to present a small threat for 2036.

NASA is also planning a manned mission to an asteroid by 2025. On Tuesday they unveiled the spacecraft that will carry a crew of four to a space rock and later to Mars.

Reporter: Paul Sutherland