Orbital period change of Dimorphos due to the DART kinetic impact

Cristina A. Thomas*, Shantanu P. Naidu, Peter Scheirich, Nicholas A. Moskovitz, Petr Pravec, Steven R. Chesley, Andrew S. Rivkin, David J. Osip, Tim A. Lister, Lance A. M. Benner, Marina Brozović, Carlos Contreras, Nidia Morrell, Agata Rożek, Peter Kušnirák, Kamil Hornoch, Declan Mages, Patrick A. Taylor, Andrew D. Seymour, Colin SnodgrassUffe G. Jørgensen, Martin Dominik, Brian Skiff, Tom Polakis, Matthew M. Knight, Tony L. Farnham, Jon D. Giorgini, Brian Rush, Julie Bellerose, Pedro Salas, William P. Armentrout, Galen Watts, Michael W. Busch, Joseph Chatelain, Edward Gomez, Sarah Greenstreet, Liz Phillips, Mariangela Bonavita, Martin J. Burgdorf, Elahe Khalouei, Penélope Longa-Peña, Markus Rabus, Sedighe Sajadian, Nancy L. Chabot, Andrew F. Cheng, William H. Ryan, Eileen V. Ryan, Carrie E. Holt, Harrison F. Agrusa

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Downloads (Pure)

Abstract

The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary asteroid (65803) Didymos, and changing the orbital period of Dimorphos. A change in orbital period of approximately 7 minutes was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement (β) was possible. In the years prior to impact, we used lightcurve observations to accurately determine the pre-impact orbit parameters of Dimorphos with respect to Didymos. Here we report the change in the orbital period of Dimorphos as a result of the DART kinetic impact to be -33.0±1.0 (3σ) minutes. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. This large orbit period change suggests that ejecta contributed a significant amount of momentum to the asteroid beyond what the DART spacecraft carried.
Original languageEnglish
Pages (from-to)448-451
JournalNature
Volume616
Early online date1 Mar 2023
DOIs
Publication statusPublished - 20 Apr 2023

Fingerprint

Dive into the research topics of 'Orbital period change of Dimorphos due to the DART kinetic impact'. Together they form a unique fingerprint.

Cite this