NASA and the ESA may mount a mission to crash a spacecraft into an asteroid and see how its trajectory is altered. Studying the impact could have major implications for protecting Earth from potential asteroid impacts in the future.
The idea of impacting an asteroid is not new, but this would be the first mission to put various theories to the test. Known as the Asteroid Impact & Deflection Assessment (AIDA) mission, it would see the ESA-led Asteroid Impact Mission (AIM) and the NASA-led Double Asteroid Redirection Test (DART) rendezvous with a binary asteroid system in 2022.
The selected system is 65803 Didymos. This consists of the Didymos asteroid, which is about 750 meters (2,460 feet) across, and the smaller egg-shaped Didymoon, 160 meters (525 feet) across. The latter completes an orbit of the former every 12 hours, at a distance of about 1.1 kilometers (0.7 miles).
Given the size of the smaller asteroid, it is thought that the NASA impactor should have a noticeable effect on its trajectory. But while the system is technically a near-Earth asteroid, fret not; there’s essentially zero chance of the asteroid being accidentally sent towards our planet, as it is stuck in orbit around its larger companion.
In the mission, AIM would be launched in October 2020, arriving in May 2022, the first spacecraft ever to visit a binary system. It would then focus its studies on the smaller asteroid, releasing three tiny satellites (CubeSats) into its orbit and also a small lander onto the surface.
In October 2022, AIM would then move to a safe distance of 100 kilometers (60 miles), and the DART spacecraft – weighing less than 300 kilograms (660 pounds) – would slam into the surface of Didymoon, watched by AIM. It is expected change the orbital period of Didymoon by up to 1%.
The video above explains how the mission would work. ESA.
AIM would not only monitor the change in trajectory of Didymoon, but also study the resulting ejected plume of material and the crater on the surface. Studying the asteroid’s interior could provide some insight into the formation of the Solar System.
"To protect Earth from potentially hazardous impacts, we need to understand asteroids much better – what they are made of, their structure, origins and how they respond to collisions," said Patrick Michel, lead of the AIM Investigation Team, in a statement. "AIDA will be the first mission to study an asteroid binary system, as well as the first to test whether we can deflect an asteroid through an impact with a spacecraft."
The mission was discussed last week at the European Planetary Science Congress (EPSC) in Nantes, France, but has yet to be formally awarded funding. Considering the amazing science the mission could return, and the implications for life on Earth, we’d be pretty disappointed if it didn’t progress further.
