VOA慢速英語：火星研究人員發(fā)現(xiàn)全行星范圍地下水系的首個證據

Mars Researchers Find First Evidence of Planet-Wide Groundwater System

火星研究人員發(fā)現(xiàn)全行星范圍地下水系的首個證據

For years, Mars has been seen as a dry, lifeless planet. But there is growing evidence to suggest this was not always the case.

多年來，火星一直被視為一個干燥、沒有生命的星球，但是越來越多的證據表明情況并非一直如此。

Scientists have already collected evidence suggesting that Mars once had a lot of water. Now, European researchers say they have discovered the first evidence of a huge groundwater system that once existed below the planet's surface.

科學家已經收集到證據表明火星曾經有過大量的水。現(xiàn)在，歐洲研究人員表示，他們發(fā)現(xiàn)了火星地表下曾經存在大型地下水系的第一項證據。

The European Space Agency, or ESA, says its Mars Express spacecraft helped discover the evidence. It said a new study provides the first geological proof that Mars once had a "planet-wide groundwater system."

歐洲航天局(簡稱ESA)稱其“火星快車號”宇宙飛船幫助發(fā)現(xiàn)了這些證據。歐洲航天局稱，一項新的研究提供了火星曾經擁有“全行星范圍地下水系”的第一項地質證據。

The study was a project of researchers from Utrecht University in the Netherlands. Francesco Salese and his team studied images of 24 deep craters in the northern half of the Red Planet. These pictures were captured by ESA's Mars Express orbiter, which was launched in 2003.

這是荷蘭烏特勒支大學研究人員的一個研究項目。弗朗西斯科·薩萊斯(Francesco Salese)和他的團隊研究了火星北半球24個深坑的圖像，這些照片是由歐洲航天局2003年發(fā)射的“火星快車號”宇宙飛船所拍攝的。

Salese is a geologist. He says scientific evidence already suggests Mars was once a watery world. "But as the planet's climate changed, this water retreated below the surface to form pools and ‘groundwater.'"

薩萊斯是一位地質學家。他表示，科學證據已經表明火星曾經是一個水世界。他說：“但是隨著這顆行星氣候的變化，這些水退到地表以下，形成水池和‘地下水’。”

His team says the images showed that large amounts of continuous groundwater activity connected the areas they studied. Evidence of basins and coastlines was also found on the surface of Mars, supporting the idea that water was once present.

他的團隊表示，圖像顯示了大量與他們所研究區(qū)域相關的持續(xù)的地下水活動。在火星表面發(fā)現(xiàn)的盆地和海岸線的證據也支持火星曾經存在水的觀點。

"There is no evidence that they had been filled from the surface, so upwelling ground water is the only remaining explanation," Salese said. He added that all the basins seemed to reach about the same height. This likely meant one large groundwater body once spread across the planet.

薩萊斯表示：“沒有證據表明它們是從表面填滿的，所以上升的地下水是剩下唯一的解釋。”他還說，所有盆地似乎都達到了相同的高度，這可能意味著一個大型地下水體曾經遍布整個行星。

The water levels seem to support evidence that an ocean may have existed on Mars between 3-4 billion years ago.

這些水位線似乎也證明三四十億年前火星曾經有過海洋。

Scientists have yet to find out what happened to all that water. "That's the big question," said Salese. "We've been able to determine that the ground water system we've discovered dates from around 3.5 billion years ago, but we don't know when or how the basins dried up."

科學家尚未找出所有這些水發(fā)生了什么事情。塞萊斯表示：“我們已經能夠確定我們發(fā)現(xiàn)的地下水系的歷史可以追溯到大約35億年前，但是我們不知道這些盆地什么時候干涸，以及如何干涸。”

Earlier research involving modeling experiments did not provide clear evidence that large bodies of water on Mars were interconnected. The latest study provides the strongest evidence yet that such bodies were linked over large areas of Mars.

早期研究涉及到模型試驗，但是它并未提供明確證據表明火星上的大量水體是相互聯(lián)系的。這項最新研究提供了最有力的證據，證明這些水體在火星的大片區(qū)域相連。

Scientists have long linked the complex history of water on Mars to whether or not life ever existed on the Red Planet.

科學家們長期以來都將火星上存在水的復雜歷史跟它是否存在生命聯(lián)系起來。

During the latest study, researchers discovered evidence of minerals within some of the identified bodies of water. Some of the same minerals have been linked to the beginnings of life on earth.

在這項最新的研究中，研究人員在一些確定水體中發(fā)現(xiàn)了礦物質的證據。其中一些相同礦物質跟地球生命起源有關。

The researchers say the finding adds weight to the idea that the water basins on Mars may have once held the materials required to support life. Some of this material could still be buried on Mars, providing possible evidence of life during future exploration.

研究人員表示，這一發(fā)現(xiàn)增加了火星水體中可能曾經擁有生命所需物質的這種觀點的份量。其中一些物質可能仍然埋在火星上，為未來探索提供可能的生命證據。

Francesco Salese believes the latest findings are not only exciting for what they teach us about Mars. He says the information could also help us learn new things about our own planet.

塞萊斯認為這項最新的研究成果不僅是因為教給我們關于火星的信息而令人興奮，他說這些信息可能也有助于我們發(fā)現(xiàn)關于地球的新事物。

"As we learn more about water on Mars - especially the reason why we see so little of it on the planet today - we may be able to find out if the same can happen to Earth, or if it had already happened when Earth was still very young," he said.

他說：“隨著我們對火星上的水了解得越來越多，特別是為何如今我們在這顆行星上看不到水的原因，我們或許能夠發(fā)現(xiàn)地球是否會發(fā)生同樣的情況，或者在地球早期是否已經發(fā)生過這種情況。”

I'm Bryan Lynn.

布萊恩·琳恩報道。