Didymos is made up of one larger asteroid with a diameter measuring 2,600 feet. And It moves in tandem with a smaller “moonlet” measuring about 525 feet (160 m) across.
NASA is aiming for the moonlet. And hoping for direct impact to slow its orbit so Earth-based telescopes will be able to do detailed studies of the impact. The plan is for the NASA spacecraft to crash onto the moonlet at an estimated 15,000 mph (24,000 km/h). And the spacecraft will be annihilated on impact.
“It will confirm for us what the viability of the kinetic impactor technique is for diverting an asteroid’s orbit and determine that it remains a viable option, at least for smaller-sized asteroids, which are the most frequent impact hazard,” Lindley Johnson, NASA’s Planetary Defense Officer, said earlier this year.
Center for Near-Earth Object Studies
NASA’s Near-Earth Object Observations Program is set up at the Center for Near-Earth Object Studies (CNEOS) in Pasadena, California on the Jet Propulsion Laboratory facility.