火星发现液态水

Liquid Water On Mars

Scientists may have found a large lake on Mars. It is under the ice near the south pole（南極）of the planet1 （see map）. It is probably made of liquid2 water that is very salty.

The scientists wanted to know what is below the ground on Mars. They used a kind of energy detector called a radar（雷达）to find out. A spacecraft（航天器）shot3 radar waves into the ground （see picture）. The way the waves bounced4 back showed something special. It could be a lake！

Scientists have been looking for water on Mars for a long time. Mars has plenty of ice， which is frozen water. It also has some water that changed to a gas in the air. We also know that liquid water has flowed on Mars before. But then it dried up. This new lake may be the first pool of liquid water found on Mars. Where there is water there could be life！

All living things need water. Water is inside our bodies. This water carries food and waste where it needs to go. Sometimes new living things form in water. Scientists will keep studying water on Mars to look for signs of life.

If people ever try to live and work on Mars， they will need water. Finding this lake may help people visit the Red Planet someday.

火星发现液态水

科学家们或在火星发现大块湖泊。它位于火星南极冰盖下方（见图），极有可能由富含盐分的液态水构成。

为了探寻火星地下构成，研究人员利用探测卫星上的雷达设备向下方发射脉冲（见图），并接受反射。当发现反射波不同寻常时，科学家们猜测这极有可能是一块湖泊！

科学家们多年来一直在持续勘探火星上的水资源。火星地表下存在大量冰层，也有部分水汽置于大气层中。我们也相信火星表面曾被水覆盖，不过之后蒸发殆尽了。如今这一发现很可能产生火星首个液态水湖泊，也进一步增加了发现外生命的可能性！

没有水，就没有生命。水是生命体的组成元素，又是营养物质与废物的运输员，因而水常常预示着生命的起源。科学家们仍将继续在火星寻找液态水，以期发现生命的迹象。

若人类欲将火星变为下一个家园，水是不可或缺的。如今看来，移民红色星球的梦想并不遥远。