I'm surprised there isn't a major push for manned missions and later colonies on Venus, for several reasons in particular: Venus's gravity is very similar to Earth's at around 0.9g. Mars is closer...
I'm surprised there isn't a major push for manned missions and later colonies on Venus, for several reasons in particular:
Venus's gravity is very similar to Earth's at around 0.9g. Mars is closer to 0.4g. Artificial gravity is little more than science-fiction at the moment, and without it the Martians of the future wouldn't even be able to set foot on Earth. Even colonists who travel to Mars and later return to Earth may be permanently impacted by the lesser gravity.
A human may die within seconds on Venus's surface where atmospheric pressures are equivalent to being 1km below the ocean and where temperatures are hot enough to melt lead, BUT the upper atmosphere may be far more habitable than even Mars and be a great place for a floating city. The atmospheric pressure in the Venusian upper atmosphere is more like Earth's and the temperature is far more bearable at about 70 degrees celsius. What would have needed a pressurised spacesuit on Mars would only need a respirator, oxygen supply and some protection from on Venus.
A colony would receive around 8 times as much solar power on Venus as they would on Mars due to its proximity to Earth.
Venus is far closer to Earth and has a more frequent launch window for optimal launches compared to Mars. This is good for minimising astronaut weightlessness and having shorter journeys.
Radiation protection is far better on Venus than on Mars. Neither planet have magnetospheres but Venus's thick atmosphere provides far more protection from solar radiation than the thin atmosphere of Mars.
On the contrary, I'm surprised there's even as much talk about colonizing Venus as there is. The entire purpose of a space colony is to be able to make use of extraplanetary resources, and lofting...
On the contrary, I'm surprised there's even as much talk about colonizing Venus as there is. The entire purpose of a space colony is to be able to make use of extraplanetary resources, and lofting yourself in the venusian atmosphere gets you access to almost none of those, and transport costs are higher than just about anywhere else in the system because of the deep Venusian gravity well, you'd have to send down a multistage rocket weighing hundreds of tons any time you wanted to bring something back. Economical transport from Venus is impossible without highly advanced non-rocket launch systems, like orbital rings, which are quite a lot more scifi than centrifugal force.
If it turns out martian gravity is insufficient for long term health, we're just going to build rotating artificial habitats like O'Neill cylinders, not lower ourselves into a ridiculously hostile, deep, and barren gravity well just because we'd weigh about the right amount there. And if Martian gravity is sufficient, it's going to be the go to colony spot for a long time because of easy transport and easy access to resources in a shallow gravity well. Given that, it's not much trouble to invest in some radiation shielding for your settlement, since that can literally just be a meter of dirt.
I don't have detailed knowledge of the technology currently employed and the feats space agencies have accomplished with them. Also not sure if you want to know why almost no people want to do...
I don't have detailed knowledge of the technology currently employed and the feats space agencies have accomplished with them. Also not sure if you want to know why almost no people want to do this (in which case it's the intimidating surface pressure and temperature, plus the sulphur present in the atmosphere), but the way I understand it:
If you just want a manned mission, you need to have all the delta-v to carry a person to Venus, plus life support. That's pretty possible. But when getting there, you also need to make a ship that can "float" or more likely, fly in the Venusian atmosphere at the 50-60 km altitude you mentioned, and then get back from there, and perhaps also back to Earth if you don't want to or can't send another rocket to carry the plane home, alongside your Earth rocket (or rockets?) carrying that ship to Venus. (Well, there's also aero-breaking but that's probably not much different than Earth, save for the sulphur.) Going from sea level to LEO takes just under 10km/s of Delta-V, and such values for 50km up in Venus's atmosphere (where the pressure is like Earth's sea level) could be assumed to be similar or slightly lower, and I'm not sure if that plus the delta-v to get back there to Earth has or could feasibly be put in a spaceplane, or whatever is built to not fall to the ground.
If you want a colony, you still need to solve the floating/flying issue, and if whatever you're sending is heavy enough, probably even getting there (and Aero-breaking whatever you're sending from orbit to flying/floating) as well, and then make the craft self-sufficient and habitable with only what's around in the atmosphere (+whatever else you send in case you feel so), which is mostly Co2, nitrogen and some sulphur.
The delta v numbers just don't work out for chemical rockets. I think the only practical way to do it would be with a nuclear thermal spaceplane, since it's got the delta v, and it could keep...
The delta v numbers just don't work out for chemical rockets. I think the only practical way to do it would be with a nuclear thermal spaceplane, since it's got the delta v, and it could keep afloat in the venusian atmosphere with nuclear jet engines more or less indefinitely. But you have to wonder what the point would be, since there's not much to explore in an atmosphere that really benefits from direct human presence. It's not like geology and other things that can be done on a planetary surface.
I'm surprised there isn't a major push for manned missions and later colonies on Venus, for several reasons in particular:
On the contrary, I'm surprised there's even as much talk about colonizing Venus as there is. The entire purpose of a space colony is to be able to make use of extraplanetary resources, and lofting yourself in the venusian atmosphere gets you access to almost none of those, and transport costs are higher than just about anywhere else in the system because of the deep Venusian gravity well, you'd have to send down a multistage rocket weighing hundreds of tons any time you wanted to bring something back. Economical transport from Venus is impossible without highly advanced non-rocket launch systems, like orbital rings, which are quite a lot more scifi than centrifugal force.
If it turns out martian gravity is insufficient for long term health, we're just going to build rotating artificial habitats like O'Neill cylinders, not lower ourselves into a ridiculously hostile, deep, and barren gravity well just because we'd weigh about the right amount there. And if Martian gravity is sufficient, it's going to be the go to colony spot for a long time because of easy transport and easy access to resources in a shallow gravity well. Given that, it's not much trouble to invest in some radiation shielding for your settlement, since that can literally just be a meter of dirt.
This. We haven't even figured out floating cities here on Earth yet.
I don't have detailed knowledge of the technology currently employed and the feats space agencies have accomplished with them. Also not sure if you want to know why almost no people want to do this (in which case it's the intimidating surface pressure and temperature, plus the sulphur present in the atmosphere), but the way I understand it:
If you just want a manned mission, you need to have all the delta-v to carry a person to Venus, plus life support. That's pretty possible. But when getting there, you also need to make a ship that can "float" or more likely, fly in the Venusian atmosphere at the 50-60 km altitude you mentioned, and then get back from there, and perhaps also back to Earth if you don't want to or can't send another rocket to carry the plane home, alongside your Earth rocket (or rockets?) carrying that ship to Venus. (Well, there's also aero-breaking but that's probably not much different than Earth, save for the sulphur.) Going from sea level to LEO takes just under 10km/s of Delta-V, and such values for 50km up in Venus's atmosphere (where the pressure is like Earth's sea level) could be assumed to be similar or slightly lower, and I'm not sure if that plus the delta-v to get back there to Earth has or could feasibly be put in a spaceplane, or whatever is built to not fall to the ground.
If you want a colony, you still need to solve the floating/flying issue, and if whatever you're sending is heavy enough, probably even getting there (and Aero-breaking whatever you're sending from orbit to flying/floating) as well, and then make the craft self-sufficient and habitable with only what's around in the atmosphere (+whatever else you send in case you feel so), which is mostly Co2, nitrogen and some sulphur.
The delta v numbers just don't work out for chemical rockets. I think the only practical way to do it would be with a nuclear thermal spaceplane, since it's got the delta v, and it could keep afloat in the venusian atmosphere with nuclear jet engines more or less indefinitely. But you have to wonder what the point would be, since there's not much to explore in an atmosphere that really benefits from direct human presence. It's not like geology and other things that can be done on a planetary surface.