Scientists had long feared that the lack of plants on Mars would also mean there wouldn't be enough oxygen to support life. But the salty water underneath the surface could store up that oxygen and provide a place for life, a new study suggests.
There might be simple animals like sponges hiding beneath that surface, the scientists report.
On Earth, life began when algae evolved photosynthesis, so that they could turn sunlight into energy. As they did, they pushed out oxygen, changing the atmosphere and filling it with the gas that allowed living things to survive.
But that doesn't happen on the surface of Mars. There is only small bits of oxygen around, and so scientists feared that there might not be life on the surface.
But a new study, published in Nature Geoscience, used computer models to explore the briny lakes underneath the Mars surface. And it found there might be oxygen lurking in those pools.
The new study found that the amount of oxygen in that briny surface could be enough to support aerobic life, according to the authors.
That oxygen is especially concentrated at the poles of the planet, the authors write. And they could help explain how the mysterious oxidized rocks found on Nasa's surface might have formed.
The study comes after scientists announced this summer that they had found a vast lake underneath the Martian surface, in a major breakthrough for the search for alien life. That discovery helped settle the long debate about whether the planet had any water at all – and the new research will add to hopes that those pools could contain life.
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