A pair of NASA spacecraft crashed into a mountain near the Moon's north pole yesterday, bringing a deliberate end to a mission that peered into the lunar interior.

Engineers commanded the twin spacecraft, Ebb and Flow, to fire their engines and burn their remaining fuel. Ebb dropped first followed by Flow about 30 seconds later.

NASA said afterwards that it had dedicated the final resting spot in honour of mission team member Sally Ride. Ms Ride was the first US woman in space. She died earlier this year.

By design, the impact site was far away from the Apollo landings and other historical sites.

Ms Ride's sister, who was in the NASA control room for the finale, said it might be time to dust off Ms Ride's first telescope to view the newly-named site.

"We can look at the Moon with a new appreciation and a smile in the evening when we see it knowing that a little corner of the Moon is named after Sally," the Rev Bear Ride said in an interview.

Since the back-to-back crashes occurred in the dark, they were not visible from Earth.

The Lunar Reconnaissance Orbiter circling the Moon will pass over the mountain and attempt to photograph the marks left by the washing machine sized-spacecraft as they hit the surface at 6,100 km/h.

After rocketing off the launch pad in September 2011, Ebb and Flow took a roundabout journey to the Moon, arriving in January on a gravity-mapping mission.

Ebb and Flow focused exclusively on measuring the Moon's lumpy gravity field in an attempt to learn more about its interior and early history.

After flying in formation for months, they produced the most detailed gravity maps of any body in the solar system.