@Homer Potvin & @Bruce Johnson I don't mean to criticize @MartinM premise at all... but the huge numbers do beg unrelated questions. Seriously, this is wonderful feedback. The aliens are of human size, not giants. The volume of the box looks way out there and totally agree. Although its not all usable space there is a lot to go around. Some thoughts... When using something like the O’Neill or McKendree cylinders you can feel these structures are in our near future. They could solve population issues or make real colonization strides within our own solar system a possibility. The question is would I ever want to live on one permanently? The useable space becomes very questionable for a ship rather than a habitat. How much would each individual need? Apart from an apartment, farmland needed for food. Here is a rabbit hole of statistics to drown in. Even with modern farming and hydroponics we are looking at a single person needing 1mn calories per year. There are 250 acres per km2, and you can expect a yield of 10-20mn calories per acre per year. Which works out to 15 people per acre. There are 250 acres in a km2 equals 975k people, let’s say a 1mn people can be fed. The original O’Neill cylinder replicating New York with 10million people looks doable, but not a great lifestyle. To get me on one of those things I’d want what I have now in terms of varied choice of food, nice housing with good entertainment and a high quality of living standard. I’m not downsizing into a lower standard, a crap deit with nothing to do but work and sleep. My aliens are leaving on a journey that could take decades to complete. Even if it's for survival of the species you won’t get many volunteers with a hardship posting like this. The ship needs to replicate life and living standards back home. Government doctrine and religious ethos help drive home the crusade we are on... The ship needs to do a lot of heavy lifting in order for it to work. However, the box dimensions I need to rethink you are correct it is way over sized... Great feedback again, many thanks this really helps MartinM.
The first problem I see, is the the Lagrange point is not a geo sync orbit. It is the point where the gravity of 2 bodies cancel each other out. I mention this because that alone would knock me right out of the story.
I never thought before about the Lagrange points for the earth and moon on either side. So I looked online to see what I would find. There are great difficulties, the sun is also a gravitational factor, but the focus is still on the earth and moon as bodies in motion, and as the third body essentially makes it an unsolvable math problem, the sun is just considered a constant that is otherwise neglected. Then you have Lagrange points that are not useful for using as a stable place for a space colony, because they are as unstable as a pencil balanced on its point, any slightest perturbing influence will drive it out from equilibrium. They are more useful for a small craft to temporarily park with much less expenditure of energy, such that there could be observations made from it.
Right, this is why they’re largely useless. The analogy I like to thing of is to imagine the gravitation field lines as contour lines on a map. The valley of 3, 4, and 5 naturally will hold a ball placed in them, but the peaks at 1 and 2 could balance a ball on them with no acceleration, moving even a little will start it rolling downhill. Anyway, I looked at the triangle maths from the previous page, and that’s also how I would do it. At that small of a section of the arc and edges so long, I can’t imagine the error from doing it the easier trig was is off by even a percent.
