Artist concept of NASA’s DART spacecraft, part of NASA’s first mission to demonstrate an asteroid deflection technique for planetary defense. Credit: NASA/JHUAPL

NASA is moving into the design phase of an ambitious test mission called the Double Asteroid Redirection Test, or DART to see if it’s capable of deflecting an asteroid out of its’ orbit.  DART is being completely implemented: designed, built and managed by scientists at the Johns Hopkins Applied Physics Laboratory.  NASA approved the concept development on June 23, 2017, and the John Hopkins team has begun the preliminary design phase.

Target Asteroid is Didymos B.

The target of the DART probe is an asteroid called Didymos – Greek for “twin”  as it’s an asteroid binary system that consists of two bodies: Didymos A, is about one-half mile (780 meters) in size, and a smaller minor planet moon orbiting it called Didymos B, about 530 feet (160 meters) in size. The DART probe would crash at about 6 km/s into the smaller of the two bodies, Didymos B. to shift its orbit.  The impact force is expected to change the speed of a threatening asteroid by a small fraction of its total velocity.  This small deflection intervention strategy will build up with time to enough of a course correction of the asteroid’s path to avoid striking the Earth.

Second synchronize mission to record results

There is a second independent mission to send an asteroid rendezvous spacecraft.  The ESA Asteroid Impact Mission (AIM) is meant to synchronize and observe the DART mission.  AIM is scheduled to launch in October 2020, and will monitor closely as DART hits Didymos B.  Aim will run detailed before-and-after crash comparisons on the structure of Didymos B, as well as its orbit, to analyze DART’s kinetic impact and the consequences.  The recorded results should provide a baseline for calibrating the force necessary to shift the orbit of any incoming asteroid, for future impact missions, especially if a real threat were to occur.