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This is Scientific American's 60-Second Science. I'm Adam Hinterthuer. Got a minute?

At Antarctica’s Blood Falls, the ice is stained red by ancient, iron-rich water pouring out of subglacial lakes formed millions of years ago. The cascading¹ water is extremely saline, has almost no oxygen and no real nutrients² to speak of. But that hasn’t stopped life from finding a niche³. According to a report in the April 17th issue of Science, a population of microbes has called the frigid⁴ place home for millennia⁵.

Even though carbon-based nutrients are missing, these microbes thrive in pockets of water trapped under the glacier⁶ by making do with what they have—which is lots of sulfates and iron. The microbes use iron molecules⁷ that the glacier scours⁸ from the bedrock to react with available sulfate, which lets the microbes then metabolize it into a useable form.

The report suggests this is one way life could have survived past eras when Earth was covered in ice. It also shows that life will spring up in the most unlikely places using some very clever chemistry. So when we’re looking for life on Mars, focus less on little green men and more on little red microbes.

Thanks for the minute for Scientific American's 60-Second Science. I'm Adam Hinterthuer.

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1 cascading
流注( cascade的现在分词 )；大量落下；大量垂悬；梯流
参考例句：
First of all, cascading menus are to be avoided at all costs. 首先，无论如何都要避免使用级联菜单。来自About Face 3交互设计精髓 Her sounds began cascading gently. 他的声音开始缓缓地低落下来。

2 nutrients
n.（食品或化学品）营养物，营养品( nutrient的名词复数 )
参考例句：
a lack of essential nutrients 基本营养的缺乏 Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。来自《简明英汉词典》

3 niche
n.壁龛；合适的职务(环境、位置等)
参考例句：
Madeleine placed it carefully in the rocky niche. 玛德琳小心翼翼地把它放在岩石壁龛里。 The really talented among women would always make their own niche.妇女中真正有才能的人总是各得其所。

4 frigid
adj.寒冷的，凛冽的；冷淡的；拘禁的
参考例句：
The water was too frigid to allow him to remain submerged for long.水冰冷彻骨，他在下面呆不了太长时间。 She returned his smile with a frigid glance.对他的微笑她报以冷冷的一瞥。

5 millennia
n.一千年，千禧年
参考例句：
For two millennia, exogamy was a major transgression for Jews. 两千年来，异族通婚一直是犹太人的一大禁忌。 In the course of millennia, the dinosaurs died out. 在几千年的时间里，恐龙逐渐死绝了。

6 glacier
n.冰川，冰河
参考例句：
The glacier calved a large iceberg.冰河崩解而形成一个大冰山。 The upper surface of glacier is riven by crevasses.冰川的上表面已裂成冰隙。

7 molecules
分子( molecule的名词复数 )
参考例句：
The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。 Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

8 scours
走遍（某地）搜寻（人或物）( scour的第三人称单数 )；（用力）刷；擦净；擦亮
参考例句：
The roasting pan scours better than pot. 烤盘比锅容易擦干净。 The best scours for UF membrane washing were 0.1%NaOH and 0.5%U10 solution consecutively washing. 0.1%NaOH 和0.5%U10溶液是理想的超滤膜清洗剂。