BBC News – Curiosity Mars rover beams images of ancient streambed
Nasa’s Curiosity rover has only been on the surface of Mars seven weeks but it has already turned up evidence of past flowing water on the planet.
The robot has returned pictures of classic conglomerates – rocks that are made up of gravels and sand.
Scientists on the mission team say the size and rounded shape of the pebbles in the rock indicate they had been transported and eroded in water.
Researchers think the rover has found a network of ancient streams.
The rocks, which were described in a media briefing at Nasa’s Jet Propulsion Laboratory in California, were likely laid down “several billion years ago”. But the actual streams themselves may have persisted on the surface for long periods, said Curiosity science co-investigator Bill Dietrich of the University of California, Berkeley.
“We would anticipate that it could easily be thousands to millions of years,” he told reporters.