Libration-induced Orbit Period Variations Following the DART Impact

0562239 - ASÚ 2024 RIV US eng J - Journal Article
Meyer, A. J. - Gkolias, I. - Gaitanas, M. - Agrusa, H. F. - Scheeres, D.J. - Tsiganis, K. - Pravec, Petr - Benner, L. A. M. - Ferrari, F. - Michel, P.
Libration-induced Orbit Period Variations Following the DART Impact.
The Planetary Science Journal. Roč. 2, č. 6 (2021), č. článku 242. E-ISSN 2632-3338
R&D Projects: GA ČR(CZ) GA20-04431S
Institutional support: RVO:67985815
Keywords : asteroid dynamics * asteroid satellites * celestial mechanic
OECD category: Astronomy (including astrophysics,space science)
Method of publishing: Open access

The Double Asteroid Redirection Test (DART) mission will be the first test of a kinetic impactor as a means of planetary defense. In late 2022, DART will collide with Dimorphos, the secondary in the Didymos binary asteroid system. The impact will cause a momentum transfer from the spacecraft to the binary asteroid, changing the orbit period of Dimorphos and forcing it to librate in its orbit. Owing to the coupled dynamics in binary asteroid systems, the orbit and libration state of Dimorphos are intertwined. Thus, as the secondary librates, it also experiences fluctuations in its orbit period. These variations in the orbit period are dependent on the magnitude of the impact perturbation, as well as the system's state at impact and the moments of inertia of the secondary. In general, any binary asteroid system whose secondary is librating will have a nonconstant orbit period on account of the secondary's fluctuating spin rate. The orbit period variations are typically driven by two modes: a long period and a short period, each with significant amplitudes on the order of tens of seconds to several minutes. The fluctuating orbit period offers both a challenge and an opportunity in the context of the DART mission. Orbit period oscillations will make determining the post-impact orbit period more difficult but can also provide information about the system's libration state and the DART impact.
Permanent Link: https://hdl.handle.net/11104/0334599