Breakthrough in Asteroid-Deflection Mission

The first-ever mission to demonstrate an asteroid deflection technique for planetary defense has moved into the final design and assembly phase, following NASA’s approval last month.

The Double Asteroid Redirection Test, or DART, being designed, built and managed by the Johns Hopkins Applied Physics Laboratory, will test what’s known as the kinetic impactor technique—striking an asteroid to shift its orbit—and take a critical step in demonstrating how to protect our planet from a potential impact.

DART’s target is the asteroid Didymos, a binary system that consists of Didymos A, about one-half mile in size, and a smaller asteroid orbiting it called Didymos B, about 530 feet across. After launch—scheduled for spring/summer 2021—DART will fly to Didymos (Greek for “twin”) and use an APL-developed onboard targeting system to aim itself at Didymos B. Then the spacecraft, about the size of a small car, would strike the smaller body at approximately 3.7 miles per second.