The editors of Science, one of the world’s leading publishers of peer-reviewed, original research, judged NASA’s two Mars rovers, Opportunity and Spirit’s accomplishments as the top scientific “Breakthrough of the Year.”

“Inanimate, wheeled, one-armed boxes roaming another planet have done something no human has ever managed,” Science reported in this week’s edition. “They have discovered another place in the universe where life could once have existed.”

Nine other scientific achievements, including discovery of another species of human, were selected as runners-up, but Science editor-in-chief Donald Kennedy said “there wasn’t much doubt about this year’s winner.”

Unmistakable proof of Martian water
Opportunity and Spirit found unmistakable proof of Martian water: rippled sediments that were once at the bottom of a shallow sea, and rock that once was so water-soaked that “it had rotted,” the journal said.

“Their finds mark a milestone in humankind’s search for life elsewhere in the universe,” Science said.

More here.