The Brainliest Answer!
There is air in space. BUT, the air is spread out that virtually you cannot make use it as a source of air for your body. The Earth has gravity, that pulls together oxygen near each other. So why Earth have oxygen but not any other planets? Well, all planets got some air but not as much to sustain life. Earth started this way. A long long time ago, there was virtually no oxygen in the planet.
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Because earth is a unique planet

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