NASA's DART Mission Alters Orbits of Dimorphos and Didymos
NASA's DART spacecraft impact on asteroid Dimorphos not only changed its orbit but also affected the trajectory of its larger companion, Didymos.
In September 2022, NASA's Double Asteroid Redirection Test (DART) spacecraft intentionally collided with the asteroid Dimorphos, aiming to alter its trajectory as a demonstration of planetary defense capabilities. The impact successfully shortened Dimorphos' orbit around its larger companion, Didymos, by approximately 33 minutes, reducing the orbital period from 11 hours and 55 minutes to 11 hours and 22 minutes.
Recent studies have revealed that this collision also affected the Didymos-Dimorphos system's orbit around the Sun. The binary system's 770-day solar orbit experienced a slight reduction of about 0.15 seconds.
The DART impact ejected a significant amount of debris from Dimorphos, contributing to the momentum change. The momentum enhancement factor was approximately two, indicating that the debris effectively doubled the impact's force.
These findings confirm that a kinetic impactor can effectively alter the trajectory of an asteroid and its companion, providing valuable insights for future planetary defense strategies.