Nasa rover Opportunity finds signs Mars once had fresh water
WASHINGTON (REUTERS) - Nasa's decade-old Mars rover, Opportunity, has found evidence that life-friendly fresh water once pooled on the red planet's surface, reinforcing similar discoveries made by newcomer Curiosity on the other side of the planet, scientists said on Thursday.
Opportunity, along with its now-defunct twin, Spirit, landed 10 years ago for concurrent 90-day missions to look for clues of the past existence of water.
Both rovers did so, confirming evidence collected by orbiting spacecraft that Mars, the planet believed to be most like Earth in the solar system, was not always the cold, dry desert that appears today.
In August 2012, Curiosity, equipped with an onboard chemistry lab, arrived for follow-up investigations to determine if Mars had other ingredients essential for supporting life.