NASA is set to demonstrate a planetary defense system against a real asteroid in three years.
The Double Asteroid Redirection Test is NASA’s first mission to demonstrate a planetary defense technique. DART will have one shot to successfully demonstrate the redirection technology. The test target is a small moonlet within the asteroid system Didymos.
The asteroid poses no threat to Earth, so researchers say it is an ideal test target. They will measure how the impact affects the trajectory of the moonlet and how it reacts with the surrounding celestial objects.
NASA has chosen such a small target because measuring the change in how the smaller asteroid orbits around the larger asteroid is much easier than observing changes in a larger asteroid's orbit around the Sun.
Several research facilities such as the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, are preparing to themselves for the mission launch in summer 2021.
To navigate the DART spacecraft to its intended target, scientists need to understand how the system behaves. Scientists have made efforts to observe Didymos from Earth since 2015. Current land-based observations using powerful telescopes will help researchers to better understand the impact made when DART slams into its target in September 2022.
The recent design changes for DART show it completing its mission by relying on small hydrazine thrusters in addition to having the ability to utilize the electric propulsion system, NASA’s Evolutionary Xenon Thruster Commercial ion engine.
“For a mission that relies on one chance, it’s a move that will provide DART with more options to ensure it hits its mark,” said Ed Reynolds, the DART project manager.
If the research is successful it may help us in the near future. A giant asteroid named Apophis has been tracked to fly right past earth on April 13, 2029. The asteroid will only be 19,000 miles away from Earth and is 1,000 times larger than the average asteroids that get this close.
NASA has assured the public that Earth will not see impact with Apophis, but if a chunk breaks off and comes directly at Earth, DART could be used in a real planetary defense emergency.