Details

Autor(en) / Beteiligte

• Agrusa, Harrison F.
• Richardson, Derek C.
• Davis, Alex B.
• Fahnestock, Eugene
• Hirabayashi, Masatoshi
• Chabot, Nancy L.
• Cheng, Andrew F.
• Rivkin, Andrew S.
• Michel, Patrick

Titel

A benchmarking and sensitivity study of the full two-body gravitational dynamics of the DART mission target, binary asteroid 65803 Didymos

Ist Teil von

• Icarus (New York, N.Y. 1962), 2020-10, Vol.349, p.113849, Article 113849

Ort / Verlag

Elsevier Inc

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• NASA's Double Asteroid Redirection Test (DART) is designed to be the first demonstration of a kinetic impactor for planetary defense against a small-body impact hazard. The target is the smaller component of the binary asteroid 65,803 Didymos. We have conducted high-fidelity rigid full two-body simulations of the mutual dynamics of this system in a broad benchmarking exercise to find the best simulation methodologies, and to understand the sensitivity of the system to initial conditions. Due to the non-spherical shapes of the components and their close proximity, the components cannot be treated as point masses and so the dynamics differ significantly from a simple Keplerian orbit, necessitating the use of numerical simulations to fully capture the system's dynamics. We find that the orbit phase (angular position or true anomaly) of the secondary is highly sensitive to the initial rotation phase of the primary, making prediction of the secondary's location from numerical simulation challenging. Finally, we show that the DART impact should induce significant free and forced librations on the secondary. If this libration can be measured by ESA's recently approved follow-up spacecraft, Hera, it may be possible to constrain properties of the secondary's interior structure. •The gravitational dynamics of Didymos were evaluated with four simulation codes.•The spin and orbital evolution are strongly coupled and non-Keplerian.•The system evolution is very sensitive initial conditions.•The DART impact should induce a considerable libration amplitude in the secondary.•We recommend that the GUBAS code be used for future DART-related dynamics studies.