Life may have been discovered in Venusian atmosphere...

I don't think Venus can realistically be terraformed.

if you settle the cloud layers, you don't need to terraform. Venus has one of the greatest and perhaps rarest gifts the human race could have received: nearly earth G. Mars cannot never will have that. Mars humans might well develop into a separate species, given time and adaptation.

Mars has close to an Earth time period in terms of hours of the day, but I don't think that's really much of an advantage. If Venus (big if ) has some kind of life , it has to be in the cloud layers. Could it be useful? Most life is. Any attempt to live in that cloud layer would have to do so without causing a threat to the native biome.

By contrast, terraforming Mars is difficult but probably possible. If there is even microbial life on Mars, and I think that's possible, than any attempt to change Mars back to a state close to what it once was, is going to have an irrevocable effect on life there. That gets tricky. Is it going to harm it or restart it? It's like bringing horses back to the Americas. They thrive without megapredators to cull their numbers, but they are not really a pest species, they're just reintroduced after millennia.

 

My understanding of Venus terraforming is it would basically involve several steps.

1. Building a gigantic solar shade at a Lagrange point which would result in total darkness.
2. Waiting until it gets so cold the CO2 mostly freezes out. The remaining nitrogen atmosphere would still be a bit too thick (3.2 bar or so) but it's closer to what we need.
3. Finding something to do with all that carbon dioxide. A tiny bit could be saved for plant life, and of course you could use some as an oxygen source. Maybe you pressurize it and store it in undeground containers? Maybe you find some method of making huge amounts of carbonate rocks?
4. When the atmosphere is reasonably well balanced to host life, you let enough light back in again to allow the formation of a stable biosphere.

The primary issue with a terraformed Venus would be the lack of any usable day night cycle due to the extremely slow (and retrograde) rotation. This can be dealt with through modifying the shade and using mirrors to light up the dark side, but it would require high technology to last indefinitely.

This stands in contrast to a terraformed Mars. If you engineered a human-breathable atmosphere on Mars it wouldn't be stable over geologic eons, but it would likely be stable over a period of tens of thousands of years, which means Martian civilization could rise, fall, and rise again without having to worry about everything going totally to shit immediately.

 

Why couldn't you just drop something into that carbon atmosphere then like algea or some lichen like plant life that would feed off that and produce oxygen, or seeds of some sort?

 

Obviously you could have all of that CO2 processed into oxygen, but an oxygen atmosphere which was super thick wouldn't be breathable by us. Not to mention it would be super flammable. Ultimately you need most of the atmospheric mass taken out of the air, and put into rocks or something.

I also forgot to mention you'd absolutely need to introduce some water to Venus via comets or something. Venus still has a tiny amount of water vapor in its atmosphere, but almost all of its original water has been lost. Despite what people think, it probably didn't "boil off." Prior to its current state it probably had a very dense wet atmosphere - well above the normal boiling point of water on the surface, but with such high air pressure, the water couldn't boil (and oddly there was no concrete surface between the air and water). But as the sun got warmer, eventually the stratosphere got warm. This was a bad thing because the "cold trap" of the stratosphere is what keeps water vapor in. Once it was gone, water vapor could float into the high atmosphere, where radiation broke it into hydrogen and oxygen. The hydrogen quickly escaped into space, and the oxygen stuck around for awhile, reacting with other things and helping to create the dense CO2 atmosphere. So the seas evaporated long before they boiled.

Note, this is also how Earth will likely eventually lose its own oceans due to the sun slowly heating up over the eons. If we're really lucky, this will begin before CO2 levels collapse to a point where photosynthesis is no longer viable - meaning the ultimate future of the Earth is a parched desert.

 

Why is this just news to some people, where do you think Venusian Aikido came from.

 

Only the Doctor knows ....... and he or she is not telling.

 

A whole lot of effort - yes. Venus, if shielded sufficiently from the Sun would be able to hold a decent atmosphere, unlike Mars - which would loose it very quickly due to it's very low gravity.

 

Also Mars doesn't have a strong magnetic field anymore does it? That would limits its ability to hold an atmosphere too, one of the reasons our planet is more suited to life.

 

Yep - and that magnetic field also aids in protecting life from the Solar wind, particle radiation etc...

 

Terraforming, in any real sense, is still a scifi concept. Unless you consider our present actions on earth terraforming, and you like hot weather. LOL

 

It is if you are working for the aliens.. /s

 

One old skool thought in the Sagan era was to guide plutinos from the outer solar system and crash them into Venus at the correct angle; blowing off its CO2 atmosphere, changing the its rotation and delivering water. I'd hate to be in charge of that project.

 

Venus supplies heat and you need that to do work any way.

An airship there just needs 14 psi to float, so the envelope IS the gondola.

The JP Aerospace airship-to-orbit concept (if it works) might be perfect.

Even rocket stages will float there.

But to make real cloud cities, you need plastics, and that means perhaps going to Titan first, what with seas of high test.

I was thinking about ways to harvest liquids.
Now, if a tether pointed at Saturn from Titan’s surface to a large container, could the tethers’ reaching deeper into Saturn’s gravity well be enough to pull great loads off a moons surface?

Cook at Venus.

There heat pipes might do work.
Harvest some CO2 and acid from the clouds to make liquid CS (tear gas) as a working fluid?

Downwards facing solar cells get light reflecting from cloud tops, and don’t forget your suicide pills in case you fall and don’t want to feel the burn...

If only I were Q for about five minutes. I’d put Venus’ atmosphere and heat on Mars, put water on both, spin one up, slow the other to 24 hours exactly....

 

In the Venusian atmosphere, a breathable mix of earth atmosphere (at the same pressure) is a lifting gas. So you can literally just float a habitat at the 1 bar level, provided you make sure the air volume to weight ratio is correct. Membrane ruptures won't be critical, because pressure will be equal on both sides of the envelope. No worries regarding gravity, radiation, energy (plenty of solar energy) , etc.

Aside from having to come up with materials which resist the corrosion of the sulfuric acid clouds, the only real issue is related to raw materials. Anything organic could be made out of stuff in the atmosphere (water, CO2, nitrogen, sulfuric acid, etc). But for metals and the like you'd need to either drop them down from orbit or find some way to get them up from the furnace below. It might be easier to use some sort of cable drag system than actively mining the surface.

The easiest thing though by far would be to just engineer things to use as little heavy materials as possible. For example, maybe you use the plentiful sunlight to grow bamboo, which you then harvest and use to make buildings.

 

Are you and Dryson related?

 

Terraforming is a thought exercise. In any other context it is a waste of effort. There is no point preparing another world for settlement when it is much easier, and possible even now, to build orbital habitats with artificial (spin) gravity suited to our species.

Planetary chauvinism aside, living on other worlds is not necessarily a bad idea, and Venus is the only one in our solar system both in the "Goldilocks Zone" and with the gravity suitable for human beings. As publius states, airships are very viable in venus, and the thick atmosphere that creates its hellish surface creates a living zone that could house as many humans in its cloud layers in floating archologies as are alive on the surface of the Earth today. If humanity is going to settle another planet I am pretty confident long term it will be Venus.

Short term, yes, we will go to Mars, but there is no more reason to stay on mars than it is to have a permanent self sustaining presence on Antarctica or Devon Island. Add to that the possible dangers posed by long term low-g, what is the benefit of Mars? Why, for that matter, is Mars much better than the Moon for settlement, but that is a separate issue.

And if by some amazing miracle Venus has a floating biosphere, it might even be of some agricultural use not yet understood.

 

We’re both chatter bots—I thought you knew that.

 

This.....

This is a fascinating idea, and what if it does harbour life in some form that whole part of the planets ecosystem is floating around in the atmosphere constantly moving about the place?