This Nasa frame grab image captured by the spacecraft’s SamCam camera October 22, 2020 shows the sampler head on Nasa’s OSIRIS-Rex spacecraft full of rocks and dust collected from the surface of the asteroid Bennu. — Nasa handout pic via AFP

WASHINGTON, Oct 27 — Nasa’s robotic spacecraft Osiris-Rex is set to begin today a delicate operation to store the precious particles it scooped up from the asteroid Bennu, but which were leaking into space when a flap got wedged open.