Double Asteroid Redirection Test: Mission Overview
Abstract
The Double Asteroid Redirection Test (DART) is a NASA mission that (i) demonstrates the kinetic impactor technique on a Potentially Hazardous Asteroid in the near-Earth population, and (ii) measures and characterizes the orbit deflection caused by the impact. DART's target is the secondary member of the binary asteroid (65803) Didymos, with the deflection experiment to occur in late September-early October of 2022. The DART impact at ~6.6 km/s will alter the binary orbital period, and this change will be measured by Earth-based observatories to confirm and quantify the amount of the deflection. The DART kinetic impact on the 160-m secondary of the Didymos system will be the first hypervelocity impact experiment on an asteroid at a realistic scale relevant to planetary defense. A key objective of this experiment is to determine the amount of momentum transfer to the target body from the kinetic impact, which is uncertain because of the recoil momentum carried by impact ejecta. DART will return new information on asteroid geotechnical properties and impact cratering on an asteroid at a scale inaccessible to laboratory experiment (an impact energy ~3 ton TNT). DART will test and validate impact modeling and simulations and advance understanding of asteroid collisional evolution. DART will carry the LICIACube satellite, a 6U cubesat contributed by the Italian Space Agency. LICIACube will be released on approach to Didymos and will perform a flyby of Didymos to obtain images of the DART impact and impact ejecta plume, in order to resolve the ejecta plume spatial structure and to study its temporal evolution. Determination of the momentum transfer from the kinetic impact will use ground-based telescopic observations of the Didymos orbital period change and DART approach phase and terminal phase imaging to locate the impact site and to characterize it, as well as imaging of the DART impact ejecta plume by LICIACube, along with modeling and simulations of the DART impact. Important detailed measurements of the Didymos system, including the mass of the secondary and the morphometry of the DART impact crater, will additionally be obtained by the ESA Hera mission, which will rendezvous with Didymos about 4 years after the DART impact, within the framework of the Asteroid Impact & Deflection Assessment (AIDA) international collaboration. DART is in its flight build phase, beginning spacecraft integration and test in April, 2020, with launch readiness date July 22, 2021.
- Publication:
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43rd COSPAR Scientific Assembly. Held 28 January - 4 February
- Pub Date:
- January 2021
- Bibcode:
- 2021cosp...43E.274C