In "day after tomorrow" sf, the recognizably familiar contemporary world is the setting for a revolutionary invention or discovery. James Blish refers to a dying breed of attic inventors. His readers remember Frankenstein, the Time Traveller, Cavor, the Invisible Man, Doctor Moreau, Robur etc. Blish's Adolph Haertel discovers anti-gravity and flies a tree hut to Mars. In CS Lewis' That Hideous Strength, scientists keep a guillotined head alive although the intelligence that speaks through the "Head" is demonic, not human. In Poul Anderson's Brain Wave, the discovery is that animal and human intelligence is increasing because Earth has moved out of an inhibiting radiation field. In all these cases, the point is that mankind interacts with the cosmos - with gravity, Mars, hyper-somatic intelligences, cosmic radiation - not just with itself. The universe waits while governments fight over parts of the Earth. (I was not leading towards that conclusion but now it seems inevitable.)
CS Lewis wrote somewhere that only the first visit to another world is of interest to a reader with imagination. We see what he meant without necessarily agreeing in detail. When a Lunar or Martian base has become an everyday environment for colonists and space travellers, then it has lost its newness. However, Anderson maintains the planet Avalon as an intriguing environment through three short stories and one novel.
Ad astra.
