Instead, Doncaster suddenly reveals that the Pluto colony was created by them as a stepping-stone to the stars, and that Earth will be left to go rancid, while "new men", like the rebuilt Sibley, conquer the universe.
Contrary to expectations, Doncaster reveals that the Pluto colony was initiated by them as an initial step towards space exploration, and that Earth will be left to deteriorate, while 'fresh pioneers', like the rebuilt Sibley, expand into the cosmos.