Jinglebell JaRock wrote:
Well, what's interesting is oxygen is buoyant on Venus. You could have floating cities filled with earth air. Not sure what that gets you, but it's true.
A space colony is vulnerable to debris and micrometeorites. You also need to keep the temperature at certain limits manually, by heating and cooling. Repairs on the outside require pressure suits. A space station has to be fully pressurized and any leak is an extremely serious issue. It's also too exposed should we be attacked by aliens in a billion years -- or by ourselves for that matter. Not to mention that the view is less homely in space, and there's that gravity thing.
If it floats in the atmosphere of Venus it might make sense to park it there. If it works in space, and it floats, it's better off in the atmosphere. You get free temperature moderator, free protection from flying junk, free weight (i.e. gravity), you can walk outside with a simple oxygen mask for short periods of time, you have more time to repair leaks, you get free clouds in the window and all these cool things.
That said, large O'Neill colonies don't require pressurization and aren't afraid of micrometeorites.