NASA/Johns Hopkins APL/Steve Gribben
Scientists on the team have been analyzing data collected from the mission since NASA’s DART probe successfully slammed into the asteroid Dimorphos last year. So far, they have published five papers in Nature, and not long ago, they confirmed that if there are enough asteroids that destroy the earth to fly to us in the future, then the DART program can be used to protect the planet.
According to data released by NASA, before DART’s main body completely collided with Dimorphos, one of its solar panels hit the asteroid at a speed of 6 kilometers per second. This was also a factor in the mission’s success, as it maximized the force of the impact. The researchers estimate that DART knocked out about 1,100 tons of debris on Dimorphos. The ejected debris flew outward away from the asteroid and generated four times the force of DART’s impact, which further changed Dimorphos’ trajectory.
While NASA only tested it on Dimorphos, scientists believe the approach would work on asteroids of similar size (about 170 meters in diameter). We don’t even need to send scouts from the earth in advance, as long as there is a few years (decades are better) warning time, then the potential risk of asteroid impact can be basically eliminated. After the European Space Agency’s Hera mission arrives at Dimorphos in 2026, we should have a clearer picture of DART’s impact on the asteroid. The mission will study the binary star system composed of Dimorphos and Didymos, and further verify the feasibility of the DART program.