DART

DART [JHU/APL]

NASA's DART (Double Asteroid Redirection Test) mission will be the first ever space mission to demonstrate asteroid deflection by a kinetic impactor. In October 2022, DART is planned to intercept the secondary member of the Didymos system, a binary Near-Earth Asteroid system with characteristics of great interest to NASA's overall planetary defense efforts.

The DART spacecraft is a simple design - a kinetic impactor with a single instrument, the Didymos Reconnaissance and Asteroid Camera for OpNav (DRACO), which will observe the asteroid upon approach. DART will navigate to crash itself into Didymos B at a speed of approximately 6 km/s, aided by the DRACO camera and sophisticated autonomous navigation software.

The DART payload, Didymos Reconnaissance and Asteroid Camera for Op-nav (DRACO), is a high-resolution imager derived from the New Horizons LORRI camera to support navigation and targeting and to determine impact site and geologic context. The spacecraft is a single-string design with thruster-only control weighing about 500 kg. The DART impact is directed at Didymos B with a relative velocity of about 6 km/s.

As a technology demonstration mission, DART also incorporates two key new technologies to further the state of the art for future missions in NASA's portfolio.

• Chemical propulsion systems store energy chemically in their propellants, but the energy created by electric propulsion systems comes from electrostatically accelerating ions formed from the propellant.
• Precise, autonomous navigation is required for DART's kinetic impact to be successful. JHUAPL has developed a Small-body Maneuvering Autonomous Real-Time Navigation (SMART Nav) algorithm for DART; it is comprised of image processing and Guidance, Navigation and Control (GNC) algorithms that are a part of a navigation simulation. When DART impacts Didymos B, navigation is handed over to the on-board SMART Nav system. In addition to the navigation, the SMART Nav fuel management logic can determine the appropriate times for course corrections to optimize the efficient use of a limited propellant supply.

DART will be launched in June 2021 from Vandenberg on a Falcon-9 v1.2 (Block 5) rocket.