While no expert (by any means) on the topic, that doesn't appear to make any sense. A gravitational slingshot maneuver is, IIRC, designed in such a way as to put the vehicle on the correct trajectory for the next leg of the journey. I may be wrong but I don't see how the planet's rotation would make any difference. Last night, I watched a program that talked a great deal about the Voyager missions. One of the missions (Voyager 2) flew past Jupiter and Saturn on to Uranus and Neptune. Now, Uranus's rotation is steeply inclined to the plane of the ecliptic (97.86 degrees). Voyager 2 had to slingshot around Uranus correctly to fly on to Neptune. If the planet's rotation seriously affected the slingshot maneuver, it seems unlikely they could've aligned the trajectory correctly. Both planets' orbits are almost inline with the plane of the ecliptic (less than 2 degrees of inclination) so it seems likely to me that Voyager had to fly a trajectory pretty close to the plane to reach the next planet. Uranus's unusual rotation would - it seems to me - have thrown the spacecraft north or south of the ecliptic if rotation was a factor. I don't think I'm explaining this well.

Here's a link to a NASA Gravity Assist Primer. I just skimmed it but I didn't see any reference to the planet rotating on its axis, just a reference to the planet's rotation around the Sun. There a link on the page to a 1.5 hour (in 4 parts) video on Trajectory Design and Gravity Assist. I don't have time to watch it now but it might be interesting.

I honestly have no idea. I will watch those video's tomorrow. If you have 30 minutes to spare, might want to listen to the Mercury Episode of Astronomy cast. They touched a bit on this talking about gravity braking. I looked up the transcript for the show, this is what they had to say:

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Eagle Eye Observatory

As they fly past, the Earth tries to slow them down, but Earth and this object are moving in the same direction, so the amount of push we can give an object heading out toward the outer solar system, that's going in the same direction of orbit we're going in, is a lot more than the pull we give it as it goes past us.

I'm pretty sure that the direction they're talking about is the planet's and spacecraft's motion around the sun, not the planet's rotation around its axis.

Right, I wasn't sure until I looked it up, at any rate, this makes L4 almost useless if you wanted to use earth for gravity assist, unless you went around the sun first.

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The More I learn, The More Ignorant I Become

Eagle Eye Observatory

Er, you can alter the day/night cycle. Just adjust the slats. Like any window.

And unless you put your station in a really poorly-planned orbit, your sunlight should be constant.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

L4 and L5 are dusty places full of micrometeoroids, and they're days from either Earth or the Moon. To start with, better have something closer to home. Build up in stages to the larger structures and more permanent, more self-sufficient settlements.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Hi IsaacKuo, post 2: I agree, except future technology may be able to approximate miminal mass shielding at 10 or 20% of the mass based shielding, besides serving other functions. The Magsail calculations for a 50 kilometer super conducting loop used a 100megawatt nuclear power plant to charge the loop in two days, if I recal correctly. The 100 megawatts would be useful for other purposes between rare days it would be needed to charge the super conducting loop. Some energy is needed continously to reliquify oxygen. The loop can also perform minor station keeping and attitude adjustment for the colony. A better mid temperature superconductor may be available soon. Even at present, liquid oxygen could be used to cool the 50 kilometer mag sail loop. A large reserve of liquid oxygen would be a valuable commodity for the colony. That large a loop can likely direct nearly all the solar wind away from all of the colony and produce a small volume of reduced galactic cosmic rays. Colonists will likely have to accept slightly reduced life expectancy due to radiation exposure. Neil

The question isn't just "can it be done", but rather "can it be done more cheaply and effectively than using mass?"

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort