When we think about humans settling on another planet, most people think of Mars.
Big names like Elon Musk have grand plans to set up a colony on Mars.
But what if there’s another planet in our Solar System worth considering?
Some scientists think that our other rocky neighbor, Venus, might be worth considering for humanity’s spread throughout the Solar System.
For one thing, Venus is a lot closer than Mars. At its closest approach, Venus is 25 million miles from Earth. On Mars’s closest approach, it is twice that distance away.
Venus also already has a thick atmosphere, which might be easier to terraform than trying to create a thick atmosphere on Mars.
But Venus’s atmosphere is mainly carbon dioxide. So the question is: How do you remove some of the Co2?
Carl Sagan once proposed seeding Venus’s thick clouds with photosynthetic bacteria that would eat up some of the carbon dioxide.
Some scientists have proposed "bombarding" Venus's clouds with hydrogen and iron aerosols to create water, which would rain down to the surface and further diminish the atmosphere.
There’s also the problem of heat. Venus’ days last nearly a full Earth year, and that slow rotation — plus the thick atmosphere — means that Venus’s global average temperature measures a searing 800 degrees Fahrenheit.
To counter the Sun’s heat and radiation, scientists have proposed solar shades to shield Venus and bring some much-needed coolness to a future human colony.
Other scientists have suggested establishing floating cities in Venus’ clouds, where the atmospheric pressure is similar to Earth’s.
Advanced Concepts Lab at NASA Langley Research Center
For now, all these ideas remain strictly theoretical.