科学家们在火星南极附近发现了三个地下湖泊。他们还证实了第四个湖泊的存在。

The chances of life surviving on the surface of Mars today are slim. The Red Planet is a desert, where temperatures routinely drop below -60C. But there might be places below ground where tiny organisms could scrape an existence. 

火星表面现在存在生命的可能性很小。这颗红色星球是一片沙漠，温度通常低于零下60摄氏度。但在地下的某些地方，微生物可能会勉强生存。

Now, scientists have confirmed the presence of four lakes about a kilometre beneath the Martian south polar ice cap. These lakes are kept liquid by large amounts of dissolved salts, which lower water's freezing point.

现在，科学家已经证实，在火星南极的冰盖下约一公里处，存在四个湖泊。这些湖泊之所以保持液态，是因为大量的溶解盐降低了水的凝固点。 

Most life on Earth doesn't tolerate such highly saline conditions, but a few specialised microbes called extremophiles do, thriving in the salty lakes of regions such as Antarctica. This raises the possibility that hardy organisms could survive today in the briny conditions below the Martian south pole.

地球上的大部分生命都无法忍受这种含盐度极高的条件，但一些被称为极端微生物的特殊微生物却能忍受，它们在南极洲等地区的咸水湖泊中繁衍生息。这就提出了一种可能性，即顽强的生物今天可以在火星南极以下的咸水环境中生存。