A space elevator's cable does not carry the same load everywhere along its length. Below geostationary altitude, gravity dominates and drags the cable toward Earth; above it, the cable's own rotation with the planet sends it flying outward instead. The cross-section right at the geostationary point has to hold up everything hanging below it, so tension peaks exactly there — and it has to stay under whatever ceiling the cable material can survive at every single altitude, or it fails at the first point that ceiling is crossed. This lab computes that tension profile live from real orbital mechanics, lets you pick a cable material's tensile strength and a counterweight mass stationed past geostationary altitude, and shows whether the resulting design can be tapered into something that holds — or whether it snaps.