Terraforming Venus #2

So, two weeks ago I focused on the issue of the heat on Venus and I made mention of the fact that the planet's rotation isn't really to my liking either. This post is going to focus on methods that could potentially change the rotational speed of Venus. I actually had this idea for a science fair project and I even got the project approved, but since it was my Senior year in high school I never followed through to actually do the project.

Venus is quite an oddball when it comes to rotation, at least compared with the other planets in our solar system. Sure Uranus kind of "rolls" around, tilted on it's side nearly 90 degrees, but Venus not only rotates slower than any of the major bodies of the solar system, it also rotates backwards. Just to be fair scientists say that its axis of rotation is tilted by more than 180 degrees, so it's still in reference to the spin we're all used to. This slow backwards rotation may have been caused by some massive collision in the past or by the gravitational influence of a neighboring planet early in the formation of the solar system. Whatever the cause it means that the planet is unlivable even if the runaway greenhouse affect is taken care of, because the surface of the planet will act more like Mercury, heating up on one side while chilling to the extreme on the other. So how can this problem be solved?

Mass Train
The first idea I had about this involved the use of a rail gun type system to create tracks all the way around the planet in a great circle that would carry massive blocks of metal (or just some really massive things) propelling them via the electromagnetic repulsion of two wires with opposing currents. This would be efficient for one thing, directing a large proportion of the electrical energy straight into the velocity of the blocks. The idea is that once the blocks reach a certain velocity the momentum will have to be conserved somehow and that means that the planet, though significantly more massive than the blocks (though not by too much), will have to start spinning faster in the direction opposing the fast moving mass train. Once the correct velocity is attained by the planet (which might take a very long time depending on the mass train's mass) the mass train would be propelled off the planet by rockets, while still moving at high speed. This would retain the respective momentums of the train and planet, and hopefully the planet could then be habitable.

Space Elevator Rockets
Another idea is to directly attach rockets that would force the planet to change its rotation just by the shear tangential forces. You can't mount the rockets on the surface because that would blow away the atmosphere (these are massive rockets) and they have to be balanced in some way so there have to be at least two (otherwise you might end up changing the planet's orbit instead). I propose that dozens of space elevators be constructed that anchor deep into the planet's crust, very deep, because we don't want parts of the planet breaking off. The rockets would be placed at the Venusian-Synchronous orbits at the tops of the space elevators. Once activated the rockets would provide enough thrust parallel to the planet's surface to change its rotational speed.

Cosmic Collisions
This option is both more difficult and easier than the others. It calls for taking existing massive objects in the solar system (comets, asteroids, small moons if they're available) and slamming them into the surface of Venus at incredibly high speeds. The easy part is altering the orbits of the material so they'll be set on a collision course with Venus. Gravity tractors or rockets could do the trick (unless you're dealing with something like a small moon, which would require something with a little more "oomph") and these could allow you to roughly direct your massive object towards Venus. One problem is getting the trajectory just right, hitting Venus at the correct angle and from the right direction is paramount. I'm sure that rockets on the object could sort it out, but then comes the next hurdle: avoiding destroying Venus, keeping the planet intact as much as possible. Small objects won't dent Venus too much but they won't change its rotational speed too much either. The larger the object the greater the damage it will do, but it makes the job generally easier by reducing the amount of objects needed. It would take a lot of time to bring in enough objects to adjust Venus' rotational speed, but at least it's an option that takes advantage of the given materials. Plus, as a side bonus, it means collisions are less likely on Earth because there are less objects to threaten Earth.

Of course the materials for all of these things would have to be incredibly sturdy, stronger than any current material made by man, but as I've said in previous posts, the scale of these projects are also currently beyond our technology, these are just options for the future.