Lagrange point colonization

Colonization of five equilibrium points in the orbit of planets or moons

Lagrange point colonization is a proposed form of space colonization^[1] of the five equilibrium points in the orbit of a planet or its primary moon, called Lagrange points.

The Lagrange points L₄ and L₅ are stable if the mass of the larger body is at least 25 times the mass of the secondary body.^[2]^[3] Thus, the points L₄ and L₅ in the Earth–Moon system have been proposed as possible sites for space colonies.^[4]^[5] The L5 Society was founded to promote settlement by building space stations at these points.

Gerard K. O'Neill suggested in 1974 that the Earth–Moon L₅ point, in particular, could fit several thousands of floating colonies, and would allow easy travel to and from the colonies due to the shallow effective potential at this point. A contemporary NASA team estimated that a 500,000-tonne colony would cost US$5.1 billion (equivalent to US$32 billion in 2023) to build.^[4]

O'Neill proposed manufacturing large cylinders or spheres as colony habitats, while others proposed an enclosed torus shape or a huge ring without a "roof". Another approach is to move an asteroid to a Lagrange point with a colony in its hollow interior.

References

^ Dorminey, Bruce (July 31, 2012). "Death Of A Sci-Fi Dream: Free-Floating Space Colonies Hit Economic Reality". Forbes. Retrieved December 17, 2018.
^ Fitzpatrick, Richard. "Stability of Lagrange Points". Newtonian Dynamics. University of Texas.
^ Greenspan, Thomas (January 7, 2014). "Stability of the Lagrange Points, L4 and L5" (PDF).
^ ^a ^b O'Neill, Gerard K. (September 1974). "The colonization of space". Physics Today. 27 (9): 32–40. Bibcode:1974PhT....27i..32O. doi:10.1063/1.3128863.
^ "The Lagrangian Points L4 and L5". pwg.gsfc.nasa.gov. NASA. Retrieved June 7, 2021.