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Conquering the LaGrange Points?

3laws_safe writes "For decades, people have dreamed about building colonies at the five LaGrange points, intersections in space where gravitational and centrifugal forces balance out to provide orbital stability. But now, the official magazine of the U.S. Space Command advocates seizing control of the LaGrange points before other nations do it. From the article: 'We face the need to control the chokepoints of the solar system.' Arthur C. Clarke, who depicted a LaGrange colony in his classic 1961 novel A Fall of Moondust, is not very happy about this. He argues we should not 'export national rivalries beyond the atmosphere.' Is he right? Or should we prepare for the fact that such rivalries are inevitable, even in space?"

11 of 911 comments (clear)

  1. Re:France by terrymr · · Score: 4, Informative

    I don't think the french have a monopoly on bureaucracy. Take a look at the paperwork requirements to make a commercial space flight from the US and then consider that you as a US citizen are prohibited from launching from another country to dodge said paperwork requirement.

  2. Re:Dimensions by Benm78 · · Score: 3, Informative

    Strictly speaking, a LP does not occupy any space at all, that's why its called a 'point' in the first place.

    If you are slightly off in any direction, you'd 'fall' further in that direction, it is more like the top of a mountain than like the bottom of a valley.

    In practice, any craft or station placed on such a point would need thrusters to stay in place, unpowered it would drift (due to solar wind, particle impact, air leaks and what not) and start 'falling'.

    I guess the region where you can reasonably compensate against falling would be quite large, depening on thruster output, weight and fuel reserves. Even if it were a sphere with a radius of 10 km, this would be a huge volume of space, and could hold many ISS-sized stations and or comsats.

  3. Re:Only FIVE such points? by doj8 · · Score: 4, Informative

    Two words: Orbital mechanics.

    There are exactly and only five Lagrange points in any pair of orbiting bodies. Three are unstable and two are stable.

    http://www.physics.montana.edu/faculty/cornish/lag range.html

    --
    -- Dan Jenkins, Rastech Inc.
  4. C'mon, spell it right by barawn · · Score: 4, Informative

    I'd be much happier if we conquered the Lagrange points first.

    It's not capitalized oddly. It's just spelled Lagrange. As in, Joseph Louis Lagrange.

  5. Re:Dimensions by barawn · · Score: 5, Informative

    L1 and L2 are unstable on the timescale of 23 days.

    L3 is unstable on a timescale of 150 years. That is, it's pretty stable for satellites, just not for planetary bodies. Of course, it also happens to be a friggin' useless orbit, as it never has line of sight visibility with Earth.

    L4 and L5 are stable, so long as the mass of the larger object is greater than 24.96 times the mass of the smaller object. (Yes, it's really that odd number: it's actually 25*((1+sqrt(1-4/625))/2) ).

    L4 and L5 are actually strange. They don't act like classical stability points, like most people think. If you push something away from L4/L5, it doesn't come back to L4/L5. It does, however, begin to orbit L4/L5, and those orbits are stable.

  6. L1 is occupied by gkwok · · Score: 3, Informative

    The Solar and Heliospheric Observatory is currently in orbit at L1.

    1. Re:L1 is occupied by barawn · · Score: 3, Informative

      None of the Lagrange points can really be "occupied". None of them are stable in the classical sense (i.e. a fixed point in space that everything falls down to). SOHO, WMAP (and in the future, JWST) will all be in orbits about the Lagrange points.

      Just because there's one thing there doesn't mean there can't be others. Plus, the ones we're mentioning here are just the solar Lagrange points. The lunar Lagrange points are all unoccupied (as far as I know...). The lunar L1/L2 are terrific places for a cheap, easy to build space elevator.

  7. As well as L2 by gkwok · · Score: 3, Informative

    L2 is occupied by the Wilkinson Microwave Anisotropy Probe, and in the future, a telescope is planned to occupy that location.

  8. Re:Yes by KaptNKrunchy · · Score: 4, Informative

    "The British Parliament offered seats to the Colonies" Sure they offered a seat or two, but not enough to make a fucking difference.

  9. Interesting Quote That Seems Appropriate by Master+of+Transhuman · · Score: 4, Informative

    I just read Justin Raimondo's latest column over at www.antiwar.com and he quotes foreign policy analyst Chalmers Johnson as follows:

    Look at the Big Picture through the perceptive eyes of foreign policy analyst Chalmers Johnson, who notes in his book, Sorrows of Empire, that conquerors of all eras have built encampments and forts in subject provinces, but there is something unique about the Americans:

    "What is most fascinating and curious about the developing American form of empire, however, is that, in its modern phase, it is solely an empire of bases, not of territories, and these bases now encircle the earth in a way that, despite centuries-old dreams of global domination, would previously have been inconceivable."

    Aside from the interest groups that benefit economically from a policy of militarism and perpetual war, and such factors as securing oil and other resources, Johnson sees

    "Something else at work, which I believe is the post-Cold War discovery of our immense power, rationalized by the self-glorifying conclusion that because we have it we deserve to have it. The only truly common elements in the totality of America's foreign bases are imperialism and militarism-an impulse on the part of our elites to dominate other peoples largely because we have the power to do so, followed by the strategic reasoning that, in order to defend these newly acquired outposts and control the regions they are in, we must expand the areas under our control with still more bases. To maintain its empire, the Pentagon must constantly invent new reasons for keeping in our hands as many bases as possible long after the wars and crises that led to their creation have evaporated."

    So now these same assholes want to dominate the entire world from the LaGrange Points.

    --
    Richard Steven Hack - This sig is TOO GODDAMN SHORT TO DO ANYTHING USEFUL WITH! MORONS!
  10. Re:Rivalries are good by Mycroft_VIII · · Score: 4, Informative

    Actually there are 5 lagrange points(as the blurb says). And I think we're talking about the earth-moon lagrange points here not earth-sun.
    The lagrange points are basically 60degrees in front of and behind the smaller object in it's orbit, between the two objets, just past the small one, and on the other side of the big object from the small one.
    Check the first link in the blurb, it'll take you to the L5 societies homepage where you can get a MUCH better explanation along with pictures.
    It's also possible to have more than one occupant at a lagrange point, as the 'point' is more like a area. While this point is a tiny space compared to the two bigger objects, it can be fairly large compared to a man made structure. Though the farther from the centre of the Lagrange point you are the more use of correctional thrusting you'll need.
    Contrary to common conception lagrange points aren't like magical peg holes that you 'lock' to when you get there, what they really are are places where if you stop there the various forces from the two larger bodies will ballance out such that you won't need to do anything to stay there. but this is the ideal, with perfect spheres and NO other gravitational souces, no solar wind, etc. So you'll always need tiny corrections from time to time, the L points just reduce this to the smallest amount, so by being willing to deal with slightly more correction you can park very near there. Again the L5 society has better info most likely, and if not google for it, I'm sure some-one has expounded with more accuracy and eloquence than I have mustered.

    Mycroft

    --
    https://signup.leagueoflegends.com/?ref=4c3ed6600b6ea