Physical properties of asteroid Dimorphos as derived from the DART impact

0585898 - ASÚ 2025 RIV US eng J - Článek v odborném periodiku
Raducan, S. D. - Jutzi, M. - Cheng, A. F. - Pravec, Petr … celkem 39 autorů
Physical properties of asteroid Dimorphos as derived from the DART impact.
Nature Astronomy. Roč. 8, April (2024), s. 445-455. ISSN 2397-3366. E-ISSN 2397-3366
Grant CEP: GA ČR(CZ) GA20-04431S
Institucionální podpora: RVO:67985815
Klíčová slova: numerical simulations * momentum-transfer * strength
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 14.1, rok: 2022
Způsob publikování: Open access

On 26 September 2022, NASA's Double Asteroid Redirection Test (DART) mission successfully impacted Dimorphos, the natural satellite of the binary near-Earth asteroid (65803) Didymos. Numerical simulations of the impact provide a means to find the surface material properties and structures of the target that are consistent with the observed momentum deflection efficiency, ejecta cone geometry and ejected mass. Our simulation that best matches the observations indicates that Dimorphos is weak, with a cohesive strength of less than a few pascals, like asteroids (162173) Ryugu and (101955) Bennu. We find that the bulk density of Dimorphos ρB is lower than ~2,400 kg m−3 and that it has a low volume fraction of boulders (≲40 vol%) on the surface and in the shallow subsurface, which are consistent with data measured by the DART experiment. These findings suggest that Dimorphos is a rubble pile that might have formed through rotational mass shedding and reaccumulation from Didymos. Our simulations indicate that the DART impact caused global deformation and resurfacing of Dimorphos. ESA's upcoming Hera mission may find a reshaped asteroid rather than a well-defined crater.

Trvalý link: https://hdl.handle.net/11104/0353540