Terraforming

To be pedantic, one could say that nearly every major body in the Solar System, save for Sol itself, is undergoing some degree of terraforming. However, for all their titanic effort, the attempts at creating self-sustaining habitats in Jupiter and the other gas giants are meagre compared to the vast resources expended in the names of Venus, Luna, and Mars.

The 'terraforming' of Earth's moon was more of an afterthought than an intentional effort. This is not to say that it wasn't planned for, but merely a consequence of having so much oxygen available in the soil. Luna's atmosphere, though not stable, is maintained by several million processing plants scattered across the surface, for the sole purpose of giving the inhabitants at the polar stations a breathable atmosphere, with about a quarter the density of Earth's, nearly all oxygen.

Aside from a slight haze and the glow of the massive polar cities, the Moon looks little different from Earth's vantage point, though it is slightly darker due to titanium dioxide being removed from the soil. The difference in the view from the Moon, however, is quite drastic during the day. It resembles a vast, white desert, with craters instead of dunes, and a dark blue, eternally cloudless sky. While there is a wind, in most cases it is a constant, gentle breeze rather than the complex dynamics of Gaia.

While alien and familiar at the same time, it is also fairly dangerous. Although the Alpha Strain possesses considerable resistance to radiation, staying out in the sun too long, even at the poles, will quickly get one sunburned.

Mars, of course, was a much more directed - and drastic - affair. While the once red planet is still somewhat chilly, and somewhat dry, rivers are flowing, oceans are forming, plants are growing and animals, if small ones, frolick among them. The last steps involved in making Mars a second Earth are being taken slowly and carefully, rather than taking even a meagre risk of failure in finishing it over the course of a year.

Mars has undergone a great deal of atmosphere-building, and flourocarbons make up a noticable fraction of the composition. Their use has been limited, primarily to avoid a potential runaway greenhouse effect - possible even on Mars. A great deal of 'derusting' has also taken place, turning Mars' reds and browns into browns and yellows and greys, and helping to build an atmosphere about half as dense as Earth's.

Although colder than Earth, there is still a great deal of water, easily covering half of the Martian surface, with more to come. Although sometimes still called the Red Planet, it most certainly isn't - even the naked eye on Earth sees a blue dot. Despite its vast oceans, Mars does not yet have quite the cloud development Earth has, due to a lack of oceanic plankton and other life, and less need for them to form. As life spreads, so will clouds and water, and soon Mars will take the same green-blue-white hues of Earth.

Solar radiation, even at Mars' distance, is somewhat harsh, but an umbrella generally suffices. Those planetary organisms that have not evolved some increased form of radiation resistance are being genetically modified to do so.

Serious attempts to terraform Venus have only begun in the last half century. It is an insanely difficult project, and is being done "because we can" rather than the delusional idea that it is more efficient than building several hundred thousand space stations. More importantly, though, people like having a planet under their feet. Hanging around in artificial or zero-g, and the risk of disastrous decompression weighs a little bit on everyone's minds. Rare as it is, everyone likes a few thousand miles of support.

A gigantic parasol hovers at the Cytherean L1 Lagrange point, completely eclipsing the Sun. This provides part of the power to the satellites surrounding the world, as well as some relief from the boiling energies they are pouring onto the surface.

A vast array of gigantic satellites and ground installations have turned the planet into a gigantic engine, and slowly, they have begun speeding the planet's rotation using over six hundred exawatts of Solar energy - by far the most energy intensive project in the Solar System. Their effect is slow, and also works to nearly rip the crust of Venus off of its mantle, easily liquifying it, but it works. Perhaps the most drastic effects are the constant, world-spanning lightning storms. Even residents on Mars saw Venus light up when the satellites were activated, and the planet is now visible year-round across the Solar System.

While the above is generally counterproductive to the end goal of making Venus habitable, it is more than compensated for by vast arrays of aerial filtration systems, scooping and sorting Venus' atmosphere from its colder, more hospitable heights. Most of these craft are actually lighter than Venus' atmosphere, as its density is so great that it can actually support the relatively heavy airships of the era.

Even with this effort, it will be centuries before Venus is a living, breathing sister world to Earth.