Originally posted by TheHorseChestnut
Interesting concept.
How would you propose they do that? Runaway Greenhouse Effect, Crushing pressure, Toxic Atmosphere and no magnetic field. Would be quite an
undertaking but maybe possible. Any ideas?
Well, the first three problems are already a step above mars-Venus is large enoguh to keep an atmosphere without losing it to solar winds, due to the
lack of a magnetic field, which you mentioned. Like Mars, it would take an unimaginable amount of cooperation and investment of resources among us
Earthlings (Wait, we could just ask Exxon..) to accomplish.
My thoughts on terraforming Venus and Mars can be looked at like a pot of soup. With Mars, you'd have to prep up your carrots, meats, broths,
veggies, what have you, then toss it into the pot and bring it up to heat. With Venus, you have all the "fixings" you need (sequestered in one
molecular form or another), except that some rival cook came and turned your temperature way up, and added some jalepones, habaneros, and scotch
bonnets into the mix. The point is, the soup is messed up, but you can start to remedy it immediately by turning down the heat.
We can't just turn down the dial for Venus, but we can put a solar shade at the
L1
Point of Venus to reduce the solar heating of the planet. Once things cool down, we can worry about fixing the 'sphere
400-500*C, a surface pressure 90 times that of earth, 300 Mph winds, and Sulfuric clouds that rain acid? Oh my! The atmosphere is admittedly very
messed, and it is no small deed to reclaim it. The atmosphere is almost completely CO2, with traces of N2. In the upper atmosphere, Sulfuric
"clouds" form, which is a layer of molecules "floating" on the denser ones beneath it. The greenhouse effect of the Co2 is so severe that, even
though 75% of light is reflected back to space by the sulfuric clouds, the little sunlight that reaches the surface is trapped, creating a temperature
hot enough to melt lead.
The density of the atmosphere itself yields one approach to terraforming. Human-breathable atmosphere is a lifting gas on Venus. So much so, that we
could construct entire floating cities using bags of (our) air. at the height these cities would operate at, the pressure is ~1 bar (same as Earth),
and the temperature is 0-50*C. These could serve as terraforming stations, growing vegetation or operating solar-powered plants that could process the
Co2.
I'm not a big fan of that one. Bombarding the volatile Venusian atmosphere could with elemental hydrogen will consume the Co2, and create graphite
(carbon) and water. This is called the
Bosche reaction.The hydrogen could be mined from the
gas giants, processed, and injected into the atmosphere. Creation of water would increase the reflectivity of the surface, lower sequester greenhouse
gases (such as Co2 and Sulfur, water vapor in the atmosphere is itself a minor greenhouse gas), and the one remaining requirement would be the
creation or introduction of a buffer gas, in this case nitrogen, into the atmosphere.
I don't know, it just seems easier to cool things down, than to heat them up. Admittedly, even if we healed the atmosphere, we'd still have to find
a way to cope with the Venesian day and night, each of which is equal to about 120 Earth days and nights. Also, I'm not a planetary scientist, I'm a
sailor. I'd love to take a cruise on Venus' oceans one day, though