Satellite of Death by Randall Garrett — Read

Five men were stationed on Earth's space satellite when the alien starship moored itself nearby. So the question -- who would investigate?

There were five aboard the orbiting wheel in the sky -- an American, a Russian, a Frenchman, an Englishman, an Indian. Their job was to keep watch -- over each other. The Wheel held enough fission-fusion bombs to blast all of Earth but the five watchdogs saw to it that those bombs remained stored, a potential threat and no more to aggressors below.