NASA and ESA team up to hijack Earth-bound asteroids

NASA will supply the collider with the Double Asteroid Impact Test (DART). It should be launched in the summer of 2021 and will fall into the smaller of the two Didymos asteroids at around 14,764 MPH. LICIACube, an Italian Cuban, will study the moment of impact. After that, ESA will launch a Hera probe in October 2024 to study the target asteroid, including the impact crater, the mass and a radar probe (the very first for an asteroid). Hera will take about two years to arrive.

Scientists chose the pair of asteroids precisely because it was easy to test. The small rock orbits slowly enough for it to be realistic to substantially alter its orbit. It would not be an option with a solo flying asteroid in a solar orbit, said ESA.

Of course, there is a big difference between a test like this and a real crisis. Although the targeted asteroid can cause serious damage to a depth of about 525 feet, it is still small and slow. A future deflection system may have to drop much larger and faster asteroids from their collision course. It is, however, an important step towards an adequate defense system, which could be enough to protect humanity against many potential impacts.