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NASA to knock asteroid off orbit for first time in 2022

Source: Xinhua| 2019-01-23 18:44:26|Editor: xuxin
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LOS ANGELES, Jan. 23 (Xinhua) -- NASA will remove an asteroid from its orbit for the first time in 2022 with its Double Asteroid Redirection Test (DART) spacecraft.

The asteroid, called Didymoon, is a moon asteroid around 150 meters tall belonging to the double asteroid system Didymos. Didymos is the most accessible asteroid of its size from Earth.

The DART spacecraft will be NASA's first attempt to demonstrate what is known as the kinetic impactor technique which will strike the asteroid to shift its orbit to defend against a potential future asteroid impact, according to a statement by Lindley Johnson, planetary defense officer at NASA Headquarters in Washington.

NASA said the DART spacecraft will achieve the kinetic impact by deliberately crashing itself into the asteroid at a speed of approximately 6 km/s. It also said the collision will change the speed of the moonlet in its orbit around the main body by a fraction of 1 percent, enough to be measured using telescopes on Earth.

The spacecraft will be launched between December 2020 and May 2021.

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