VOA慢速英语2019 火星研究人员发现火星地表下曾有大型地下水系的首个证据

Mars Researchers Find First Evidence of Planet-Wide Groundwater System

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

多年来，火星一直被视为一个干燥、没有生命的星球，但是越来越多的证据表明情况并非一直如此。

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.

科学家已经收集到证据表明火星曾经有过大量的水。现在，欧洲研究人员表示，他们发现了火星地表下曾经存在大型地下水系的第一项证据。

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.”

欧洲航天局（简称ESA）称其“火星快车号”宇宙飞船帮助发现了这些证据。欧洲航天局称，一项新的研究提供了火星曾经拥有“全行星范围地下水系”的第一项地质证据。

The study was a project of researchers from Utrecht University in the Netherlands. Francesco Salese and his team studied images of 24 deep craters² in the northern half of the Red Planet. These pictures were captured by ESA’s Mars Express orbiter, which was launched in 2003.

这是荷兰乌特勒支大学研究人员的一个研究项目。弗朗西斯科·萨莱斯（Francesco Salese）和他的团队研究了火星北半球24个深坑的图像，这些照片是由欧洲航天局2003年发射的“火星快车号”宇宙飞船所拍摄的。

Salese is a geologist³. He says scientific evidence already suggests Mars was once a watery⁴ world. “But as the planet’s climate changed, this water retreated below the surface to form pools and ‘groundwater.’”

萨莱斯是一位地质学家。他表示，科学证据已经表明火星曾经是一个水世界。他说：“但是随着这颗行星气候的变化，这些水退到地表以下，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.

他的团队表示，图像显示了大量与他们所研究区域相关的持续的地下水活动。在火星表面发现的盆地和海岸线的证据也支持火星曾经存在水的观点。

“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.

萨莱斯表示：“没有证据表明它们是从表面填满的，所以上升的地下水是剩下唯一的解释。”他还说，所有盆地似乎都达到了相同的高度，这可能意味着一个大型地下水体曾经遍布整个行星。

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

这些水位线似乎也证明三四十亿年前火星曾经有过海洋。

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.”

科学家尚未找出所有这些水发生了什么事情。塞莱斯表示：“我们已经能够确定我们发现的地下水系的历史可以追溯到大约35亿年前，但是我们不知道这些盆地什么时候干涸，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试验，但是它并未提供明确证据表明火星上的大量水体是相互联系的。这项最新研究提供了最有力的证据，证明这些水体在火星的大片区域相连。

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

科学家们长期以来都将火星上存在水的复杂历史跟它是否存在生命联系起来。

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.

在这项最新的研究中，研究人员在一些确定水体中发现了矿物质的证据。其中一些相同矿物质跟地球生命起源有关。

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.

研究人员表示，这一发现增加了火星水体中可能曾经拥有生命所需物质的这种观点的份量。其中一些物质可能仍然埋在火星上，为未来探索提供可能的生命证据。

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.

塞莱斯认为这项最新的研究成果不仅是因为教给我们关于火星的信息而令人兴奋，他说这些信息可能也有助于我们发现关于地球的新事物。

“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.

他说：“随着我们对火星上的水了解得越来越多，特别是为何如今我们在这颗行星上看不到水的原因，我们或许能够发现地球是否会发生同样的情况，或者在地球早期是否已经发生过这种情况。”

I’m Bryan Lynn.

Words in This Story

retreat – v. to move back or withdraw

basin – n. low area of land from which water flows

determine – v. discover the facts or truth about something

geologist – n. a scientist who has studied rocks and soil in order to learn about the history of planets

crater¹ – n. a large hole in the ground

1 crater   

n.火山口，弹坑

参考例句：

• With a telescope you can see the huge crater of Ve-suvius.用望远镜你能看到巨大的维苏威火山口。
• They came to the lip of a dead crater.他们来到了一个死火山口。

2 craters   

n.火山口( crater的名词复数 )；弹坑等

参考例句：

• Small meteorites have left impact craters all over the planet's surface. 这个行星的表面布满了小块陨石留下的撞击坑。 来自《简明英汉词典》
• The battlefield was full of craters made by exploding shells. 战场上布满弹坑。 来自《现代英汉综合大词典》

3 geologist   

n.地质学家

参考例句：

• The geologist found many uncovered fossils in the valley.在那山谷里，地质学家发现了许多裸露的化石。
• He was a geologist,rated by his cronies as the best in the business.他是一位地质学家，被他的老朋友们看做是这门行当中最好的一位。

4 watery   

adj.有水的，水汪汪的；湿的，湿润的

参考例句：

• In his watery eyes there is an expression of distrust.他那含泪的眼睛流露出惊惶失措的神情。
• Her eyes became watery because of the smoke.因为烟熏，她的双眼变得泪汪汪的。