Outcome of the Dart Mission, the First Planetary Defence Experiment

Campo Bagatin, Adriano; de León, Julia; Küppers, Michael; Benavidez, Paula G.; Santana-Ros, Toni; Martínez Parro, Laura
Referencia bibliográfica

Seventh edition of the Spanish Meeting of Planetary Sciences and Exploration of the Solar System (7th CPESS

Fecha de publicación:
7
2023
Número de autores
6
Número de autores del IAC
1
Número de citas
0
Número de citas referidas
0
Descripción
On the 26th of September, 2022, at 23:14 UT, the APL/NASA Double Asteroid Redirection Test (DART) spacecraft impacted successfully on the secondary of the NEA binary asteroid (65803) Didymos, after a 10 months travel. [1] The 589 kg spacecraft impacted Dimorphos at 6.14 km/s, and images of the system were taken by the DRACO camera onboard DART prior to collision. Images of the impact outcome were taken about 3' after impact by the Italian LICIA cubesat, from a minimum distance of 55 km. [2] Images reveal that the primary of the Didymos system is not top-shaped, contrarily to what expected from radar observations. Dimorphos was an oblate spheroid [3], which shape is at odds with the expected tri- axial shape (prolate) predicted by tidal theory. Ground based and HST observations were used to measure the change in orbital period of Dimorphos, and anestimation of the amountof mass ejected is given. Orbital period was shortened by 33' [4] with respect to the original 11.92 h period, which implies a velocity vector change of 2.7 mm/s [1]. The collison triggered a structured tail that was observed to persist at least 7 months after the impact [5,6], making the first human-made active asteroid [7]. Results of the mission are reported and discussed.

[1] Cheng, A. et al. (2023) Nature. 224, 457

[2] Dotto, E. et al. (2023) Nature. In press

[3] Daly. T. et al. (2023) Nature. 224, 443

[4] Thomas, C. et al. (2023) Nature. 224, 448

[5] Li. J.-Y. et al. (2023) Nature. 224, 452

[6] Graykowsky et al. (2023) Nature. 224, 461

[7] Tancredi, G. et al. (2023) MNRAS. 522, 2403