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.
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.
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."
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.
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.'"
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.
"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.
The water levels seem to support evidence that an ocean may have existed on Mars between 3-4 billion years ago.
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."
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.
Scientists have long linked the complex history of water on Mars to whether or not life ever existed on the Red Planet.
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.
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.
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.
"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.
I'm Bryan Lynn.
1.climate change 气候变化
Carbon emissions exacerbate the global climate change problem.
2.find out 发现
I hope we can find out about it.
3.dried up 干涸
The spring dried up long ago.
4.ground water 地下水
Ground water is simply water that occupies the open spaces in the soil and rock.
5.His team says the images showed that large amounts of continuous groundwater activity connected the areas they studied.
large amounts of 大量的
Earthworms consume large amounts of soil, and produce a rich humus, perfect in texture.
The company has invested large amounts of funds and manpower for the development of new products.
6."There is no evidence that they had been filled from the surface.
There is no evidence that 没有发现...证据
There is no evidence that the broker was in league with the fraudulent vendor
Contrary to popular belief, there is no evidence that what you look like makes much difference to your life.
科学家已经收集到证据表明火星曾经存在过大量的水 。现在，欧洲研究人员表示，他们发现了火星地表下曾存在大型地下水系的首份证据 。
欧洲航天局（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首份地质证据，证明火星曾经拥有“全行星范围地下水系” 。
这项研究是荷兰乌特勒支大学研究人员的项目 。弗朗西斯科·萨莱斯（Francesco Salese）及其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”宇宙飞船拍摄的 。
萨莱斯是一位地质学家 。他表示，科学证据已经表明火星曾是一个水世界 。他说：“但随着火星的气候变化，这些水退到地表以下，形成了水池和‘地下水’ 。”
他的团队称，这些图像显示出与他们研究区域有关的大量持续的地下水活动 。在火星表面也发现了盆地和海岸线的证据，这也支持了水曾经存在的观点 。
萨莱斯表示：“没有证据表明它们是从地表被填满的，所以上升的地下水成为唯一的解释 。”他还说，所有盆地似乎都达到了相同的高度，这可能意味着一个巨型地下水体曾遍布整个星球 。
科学家尚未发现这些水的下落 。塞莱斯表示：“这是个大问题 。我们已经确定，我们发现的地下水系可追溯到大约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 。”
早期的建模实验研究并没有提供明确的证据，表明火星上的大片水域是相互关联的 。最新的这项研究提供了迄今为止最有力的证据，证明这些水体在火星的大片区域内是相互关联的 。
在最新的这项研究中，研究人员发现了一些在已确认的水体中含有矿物质的证据 。其中一些相同矿物质与地球生命起源有关 。
研究人员表示，这一发现进一步证实了火星盆地中可能存在维持生命所需物质的这一观点 。其中一些物质可能仍然深埋于火星上，为未来探索提供可能存在生命的证据 。
塞莱斯认为，最新的研究成果让我们对火星有了更新的认识，这令人兴奋 。他说，这些信息还有可能帮助我们了解有关地球的新事物 。