|MadSci Network: Astronomy|
The answer to the first part of your question is easy: Yes, humans will probably be able to live on Venus in the future.
The second part is more involved, and begs a further question: Would we want to live on Venus?
My answer to that question is: Probably not. Here's why.
People often call Venus the "sister planet" to Earth since the two are similar in physical size. But there are significant differences: because it's closer to the sun, Venus gets 125% more sunlight than Earth. Atmosphere at the surface is 90 times more pressurized and 50 times denser than on Earth, not to mention poisonous-- 96% carbon dioxide, no oxygen. This also causes a permanent greenhouse effect which keeps the entire planet superheated to over 800° Fahrenheit during the "day"-- which, incidentally, lasts more than eight months due to Venus' slow rotation.
We could build pressurized, air-conditioned habitats underground. But unless we shield the surface from sunlight, the surrounding geology will still get lethally hot during "daytime". We might venture above ground for a few hours at a time, but we'd have to scurry back before our pressure suits melted from the heat and corrosive atmosphere.
Maintaining habitats in this environment would be expensive and difficult. And really, what benefits would we derive from living on Venus? The air is poisonous and too thick for telescopes to see through. The deadly surface conditions would make mining or building anything a money pit. We couldn't grow any plants or animals, except maybe microscopic ones, and we don't need a whole planet for that. Do we really want the elbow room if it's going to burn our arms off?
Anyway, we've been talking about a short-term residence, like putting a capsule on the ocean floor for a few weeks. If Venus is to be a permanent home, we'd want to be able to survive above ground with a minimum of risk. That means altering surface conditions, which means planet-wide terraforming.
We have many theoretical options in this arena. One netizen has suggested dumping vast quantities of liquid nitrogen into Venus' atmosphere to transform the native gases into something less lethal. Another proposes the construction of floating cities in the upper atmosphere. And every other would-be world-builder advocates slamming ice comets into the equator to speed up the planet's rotation, thus shortening its "day" and reducing the heat problem.
But all these approaches would be prohibitively expensive and complicated. If humans are still puttering around the Solar System when we have such technology, we'll probably have better things on which to spend our time and money. In the meantime, Mars is a much better place to build a second home.
To paraphrase an old saying: Just because we can live somewhere, doesn't mean we should live there.
Hope this helps!
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