不久前，著名的《科学》杂志评选出2004年最重要的十大科学发现。这些发现中既有人类对神秘宇宙太空的探索，也有对身边熟悉事物的新发现。无论是何种的科学探索和发现，人类求知的愿望和动力永远都在推动社会的发展和进步。

Water and robots on Mars chosen as tops in 2004 by 'Science'

WASHINGTON — The conclusive discovery by a pair of wheeled robots that Mars once had vast pools of water and possibly could have harbored life was chosen by the editors of the journal Science as the most important scientific achievement of 2004.

Scientists announced in March that the Mars once played host to salty seas. This Mars Express image indicates water erosion.  

NASA's two Mars rovers（漫游者）Opportunity and Spirit, landed on the Red Planet early in 2004 and have since found clear and conclusive evidence that Mars was drenched with（浸透） water at some time in its history. 

The editors of Science, one of the world's leading publishers of peer-reviewed, original research, judged the robotic accomplishment 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." 

Opportunity and Spirit found unmistakable proof of Martian water: rippled sediments（沉积物） 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. 

Kennedy said one of the most important messages from the remote exploration is "the extraordinary efficiency of these robot missions." 

He said it is clear that the National Aeronautics and Space Administration must not abandon its robotic exploration while gearing up for President Bush's program to send humans to the moon and later to Mars. 

"To do one at the expense of the other would be a mistake," Kennedy said. "It remains to be demonstrated what a human exploration could do that we can't do now or couldn't do in the next 10 years with robotic technology." 

The first runner-up for breakthrough of the year was the discovery on the Indonesian island of Flores of fossils from a species of tiny humans who stood about 3 feet tall and had a brain less than a third the size of modern humans. Yet, the diminutive（小的） hominid（原始人） lived about 18,000 years ago. This suggests that Homo floresiensis shared the Earth with Homo sapiens（人类）, or modern people. Science said some described the find as "the biggest discovery in half a century of anthropological research."liuxuepaper.com