Which NASA mission first landed a spacecraft on an asteroid’s surface?

NASA’s NEAR Shoemaker first landed a spacecraft on an asteroid’s surface.

The Near Earth Asteroid Rendezvous mission entered orbit around 433 Eros in February 2000. On February 12, 2001, it completed the first controlled landing on an asteroid, even though landing had not been part of the original primary mission plan. The spacecraft continued transmitting scientific data from the surface for a short time.

NEAR Shoemaker is often confused with NASA’s earlier claim that it became the first spacecraft to orbit an asteroid; that milestone also belongs to NEAR Shoemaker, at Eros. Dawn later orbited Vesta and Ceres, while Japan’s Hayabusa returned samples from asteroid Itokawa. NEAR did not return asteroid samples to Earth.