NASA spacecraft to crash into small moonlet to demonstrate its planetary defence technique

In its first mission to demonstrate a planetary defence technique, the US space agency NASA on Monday revealed its plan to hit a small moonlet target in a double asteroid system with a spacecraft in 2022. Commenting on the development, Andy Rivkin, a co-lead of the investigation team said, "The Didymos system is too small and too far to be seen as anything more than a point of light, but we can get the data we need by measuring the brightness of that point of light, which changes as Didymos A rotates and Didymos B orbits.” Researchers are still not certain about the target's composition: whether it is composed of solid rock, loose rubble or "softer" sand. The spacecraft, called Double Asteroid Redirection Test, will carry an optical navigation system to capture images that help the spacecraft reach its target. The DART spacecraft will crash itself into the asteroid at a speed of approximately six kilometer per second and the collision will change the speed of the moonlet in its orbit around the main body by a fraction of one per cent, enough to be measured using telescopes on the Earth, according to the NASA.