There's an enormous amount of Golden Age sf that isn't concerned with those things, however. The majority of work by C. M. Kornbluth, Lester del Rey, Henry Kuttner and C. L. Moore (together or separately), L. Sprague de Camp, Ray Bradbury (though he was more of a fantaisiste using science-fictional tropes), Theodore Sturgeon, Cordwainer Smith, Frederik Pohl... even a fair chunk of Cordwainer Smith and Robert A. Heinlein, were more concerned with other things rather than space travel and aliens.
Science fiction -- as with any worthwhile literature -- is driven by the concerns of its times, and a lot of sf dealt with earth-bound issues (albeit often in the form of the future of current trends). The Foundation books are (quite rightly, I'd say) considered among the cornerstones of Campbellian sf. Very little of Asimov, by the way, has aliens; and as for "rockets" -- I assume you mean space-traveling vehicles, as rockets proper would severly limit travel... in which case, there's quite a bit of that going on in the Foundation books... a galactic empire, for one thing, which requires an enormous amount of such; not to mention the space chase concerning the Mule, or in search of the Second Foundation, etc. Space battles are in Foundation, there's a fair amount of shiny technology (a type of sf which George O. Smith excelled in, and he was also -- quite rightly -- considered to be one of the great exemplars of Golden Age sf)... all these hallmarks of Golden Age sf are the trilogy....