The mission follows directly from DART, which deliberately struck the asteroid in 2022 to test whether a spacecraft collision could alter an asteroid’s path. Hera’s arrival marks the next phase of that experiment, returning to the same target to assess what the impact actually did.
Hera has started close inspections of Dimorphos, the asteroid struck by DART. The spacecraft is conducting its observations four years after the collision. Its goal is a detailed assessment of the deflection’s effects on the asteroid.
DART demonstrated that a spacecraft could hit an asteroid. Hera’s work quantifies how well that collision worked, data described as essential to designing any real planetary defense response. The mission closes the loop on the first full-scale planetary defense experiment.
With Hera now at Dimorphos, its detailed measurements of the impact effects are the next milestone in the planetary defense effort begun by DART.
