Image copyright NASA Image caption The Osiris-Rex space probe will travel through space for two years before it lowers itself to the surface of a space rock
A Nasa spacecraft called Osiris-Rex will crash into an asteroid in 2020 to test planetary defence techniques.
The impactor will seek out a rock that is roughly 300m wide and more than 5m deep and drop a thruster onto its surface.
A craft from Japan will take images and use the data to plan future missions to the asteroid.
The Osiris-Rex probe and its craft companion, the Hayabusa-2, are due to arrive in space in June 2020.
How will the spacecraft work?
New scientific research will be conducted from the far side of the moon, where the scientists hope they will measure tiny changes caused by asteroids impacting with the lunar surface.
The asteroid to be targeted, NE14, will be hit by a tiny 0.02mm-diameter thruster – only the size of a grain of salt – which would cause a very loud bang.
If the mission is successful, the Solar System Observations in the Near-Earth Orbit (SpaceX) mission will use the data collected from these tiny nasties to find threats in the inner solar system.
The object could either be considered benign or potentially dangerous, depending on where it falls on the relative “radiance spectrum” of light.
Where will the spacecraft land?
The spacecraft will fly through space for two years before slowly bringing itself down to the surface of NE14.
“NASA will capture this asteroid as it is passing through the inner solar system,” said Dr Stephen Stiglitz, associate administrator for the Exploration Systems Mission Directorate (ESMD) at NASA Headquarters in Washington.
A camera from the Hayabusa-2 craft will be able to detect the impact, and will record the resulting collision.
The spacecraft will not be observed from space itself. Instead, an infrared light laser from the Hayabusa 2 craft will be used to confirm that the touchdown actually took place on the asteroid’s surface.
SATMOSPHERE – Mapping Asteroid Redirection Techniques Most simple – Planck collects the light from gas that surrounds asteroids in space from one direction and beams it through space back to Earth
Planck collects the light from gas that surrounds asteroids in space from one direction and beams it through space back to Earth Impossible – The aliens would have to change the orbits of the sun, Jupiter and Saturn to shift the asteroids from their original direction
The aliens would have to change the orbits of the sun, Jupiter and Saturn to shift the asteroids from their original direction Impossible – Our mechanism does not work; the asteroids are too big
Our mechanism does not work; the asteroids are too big Impossible – Our satellite works, but the orbits of the planets are too irregular
Our satellite works, but the orbits of the planets are too irregular Impossible – Our solar system-wide environment has to be altered to redirect an asteroid
The wreckage of the Osiris-Rex craft, and any debris that survived the impact, will be sent to researchers at UCLA in Los Angeles to investigate.
How long until NASA knows if it has found a “dirty bomb” target?
If the mission is successful, Osiris-Rex could be the first spacecraft that the Planetary Defence Coordination Office can point to a potential NEO (Near-Earth Object).
It could also help prepare space agencies around the world for planetary defence in the future.
The collision test will be filmed with a movie camera and a microphone and is expected to last up to an hour.
Another impact mission has also been proposed by the ESA’s (European Space Agency) Rosetta probe.
The spacecraft – due to pass Rosetta’s target, comet 67P/Churyumov-Gerasimenko, in October this year – could use the radio signals from the comet to scan for Earth-like asteroids that could pose a danger.