'Voice' of Curiosity Mars rover touch-down
The US space agency's Curiosity rover remains perfectly on course to make its Monday (GMT) touch-down on the Red Planet.
The entry, descent and landing (EDL) is a fully automated procedure. Nasa will be following events at its mission control at the Jet Propulsion Laboratory in Pasadena, California.
Allen Chen, the EDL operations lead, is tasked with calling out the milestones as the rover tries to get down to the surface. His is the voice the world will hear on TV.
He told our correspondent Jonathan Amos about his role.