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                      |                                                       | NASA has a plan to knock an asteroid off course |                              |  |                              | DART stands for Double Asteroid Redirection Test. NASA is planning the DART mission for launch in 2021. It'll visit a double asteroid - Didymos and its tiny moon - and crash into the moon in an attempt to change its orbit. Read more. |                              |  |  | 
                      |                                                       | ESA will head for the double asteroid, too |                              |  |                              | Following NASA's DART mission, if all goes as planned, a European Space Agency mission called Hera will also visit Didymos and its moon, to gather vital, detailed information. Watch a video, where astrophysicist and Queen guitarist Brian May explains more. |                              |  |  | 
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