A Nasa spacecraft has successfully slipped into orbit around the moon.
A roomful of scientists and engineers monitoring the New Year's Eve manoeuvre clapped after the Grail-A probe signalled that it was circling the moon.
The celebration was brief. Mission team members looked ahead to when its twin Grail-B was scheduled to perform the same move.
The duo will study the moon's gravity to determine what is inside straight down to the core.
The 496 million US dollar mission is managed by the Nasa Jet Propulsion Laboratory.