The answer may be that virtually all the water on Mars is now locked in the permafrost layer under the surface, with more contained in the planet's polar caps.
答案可能是,现在火星上几乎所有的水都被锁在地表下的永久冻土层中,更多的水被包含在这个星球的极地冰帽中。
Geologists think that this fluidized ejecta crater indicates that a layer of permafrost, or water ice, lies just a few meters under the surface.
地质学家认为,这个具有流体化喷出物的陨石坑表明,在地表下几米深处有一层永久冻土层或水冰。
Beneath this active layer is a second layer called "permafrost", which is frozen all year around, and is impermeable to water.
在这一活跃层下面,是被称为“多年冻土”的第二层,终年冻结,不透水。
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