DART impacting the smaller of the two Didymos asteroids, as seen from the larger body. NASA’s Double Asteroid Redirect Test, DART, mission is due to be launched in late 2020. The fridge-sized spacecraft will fly itself to the Didymos system with a xenon-based electric propulsion system, steering with an onboard camera and sophisticated autonomous navigation software. DART will reach Didymos in October 2022 and steer itself into Didymoon at a speed of approximately 6.6 km/s. ESA's desk-sized Hera spacecraft would then reach Didymoon in 2026 for a close-up survey of the results.