Of all the planets, Mars is our closest relation in terms of makeup (not distance), but that’s not saying much. And it certainly doesn’t mean that the red soil is hospitable. The atmosphere of Mars differs from the Earth’s in many ways, and most of them don’t bode well forhumans living there.
- It’s composed mostly of carbon dioxide (95.3 percent compared to less than 1 percent on Earth).
- Mars has much less nitrogen (2.7 percent compared to 78 percent on Earth).
- It has very little oxygen (0.13 percent compared to 21 percent on Earth).
- The red planet has about 1/1000 as much water vapor (0.03 percent).
- It exerts only 7 millibars of pressure (Earth’s atmospheric pressure is 1,000 millibars).