Project Sponsor : NASA 

Start Date : 11/24/2021

Faculty Investigator : Dr. Masatoshi “Toshi” Hirabayashi

Project Status : Completed

DART was NASA’s first planetary defense mission dedicated to demonstrating asteroid deflection by changing an asteroid’s motion through kinetic impact.  

DART spacecraft successfully impacted Dimorphos, the secondary component of the near-Earth binary asteroid system (65803) Didymos on September 26, 2022 (UTC). The orbit period of Dimorphos was reduced by about 33 min, which corresponds to Dimorphos’s orbital velocity change of about 2.7 mm/sec.  
 
As members of DART Dynamics Working Group, we investigate how Didymos system’s mutual dynamics are affected by the impact-related perturbations such as ejecta falling onto the surface, crater formation, and global shape change. These investigations are crucial for properly interpreting the remarkable achievements of the DART mission for future planetary defense missions. 

Associated Publications:
– Cheng, A. F., Agrusa, H. F., Barbee, B. W., et al., Momentum transfer from the DART mission kinetic impact on asteroid Dimorphos, 2023, Nature, 616, 457 
Hirabayashi, M., Ferrari, F., Jutzi, M., et al., Double Asteroid Redirection Test (DART): Structural and Dynamic Interactions between Asteroidal Elements of Binary Asteroid (65803) Didymos, 2022, The planetary science journal, 3, 140 
Nakano, R., Hirabayashi, M., Agrusa, H., F., et al. NASA’s Double Asteroid Redirection Test (DART): Mutual Orbital Period Change Due to Reshaping in the Near-Earth Binary Asteroid System (65803) Didymos, 2022, The Planetary Science Journal, 3, 148   
– Richardson, D. C., Agrusa, H. F., Barbee, B., et al., Predictions for the Dynamical States of the Didymos System before and after the Planned DART Impact, 2022, The planetary science journal, 3, 157