3 ms·
> You can think of it like going around the top of a hill I always wondered: a ball is not stable on a hill since you have to balance it on the top, but a ring
by Chris2048 5y ago
> You can think of it like going around the top of a hill
I always wondered: a ball is not stable on a hill since you have to balance it on the top, but a ring is. Could a large ring-size space-station be stable at these points by having them at their centre?
EDIT: looking here: https://www.youtube.com/watch?v=JZj9zINN3e0 https://www.youtube.com/watch?v=JZj9zINN3e0 it looks like more of a saddle. So maybe a space station of 2 parts tethered together with their centre-of-mass at L2? Since space is frictionless (as opposed to an actual saddle surface) I guess there will still need to be station-keeping, but only in on direction: maybe my allowing synchronised "ballast" weights to fall in/outwards.
- pierrec 5y agoI think the metaphor only sort-of works when you represent the object as a point. The farther you are from an unstable point of equilibrium, the harder you're getting pushed away from it. So if your station gets nudged, the farther part will push the station away harder than the closer part. Overall it probably changes nothing about how much effort is required to keep the station in place.