WASHINGTON-The U.S. space agency NASA has revealed details about its plan to hit a small moonlet target in a double asteroid system with a spacecraft in 2022, its first mission to demonstrate a planetary defense technique.
The asteroid, called Didymoon or Didymos B, is a moon asteroid around 150 meters tall orbiting a larger body Didymos A, the most accessible asteroid of its size from Earth. An international campaign is now making observations using powerful telescopes worldwide to understand the state of the asteroid system. “The Didymos system is too small and too far to be seen as anything more than a point of light, but we can get the data we need by measuring the brightness of that point of light, which changes as Didymos A rotates and Didymos B orbits,” said Andy Rivkin, a co-lead of the investigation team. Researchers are still not sure about the target’s composition: whether is is composed of solid rock, loose rubble or “softer” sand. A softer surface would absorb much of the impact force and may not be pushed as drastically as if a spacecraft hit a harder surface.
But the NASA team will eventually see the asteroid system close-up thanks to an Italian-made imager. The shoebox-sized cube satellite will record the spacecraft’s impact and its aftermath.