More like Uncertainty

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CavorSeries
series2 books1901
About aliens, set in the moon and underground & caves.
“H. G. Wells's 1901 novel The First Men in the Moon is narrated by the businessman Bedford, who joins the reclusive scientist Cavor after Cavor invents cavorite, a gravity-blocking substance that carries the two men to the Moon.”
from the catalogue
Start with The First Men in the Moon →
Known SpaceUniverse
universe142 books1964
About aliens, set in far future.
“Give a clever species a few centuries and a working fusion drive, and it will fill the sky with problems.”
from the catalogue
Start with Ringworld →
includes Ringworld, Fleet of Worlds, Man-Kzin Wars
Starman JonesNovel
Robert A. Heinleinstandalone novel1953
Space opera, about coming of age, set in far future.
“Starman Jones, a 1953 science fiction novel by Robert A. Heinlein, features a farm boy who wants to go to the stars.”
from the catalogue
A Columbus of SpaceNovel
Garrett P. Servissstandalone novel1911
Adventure, about aliens, set in venus & inner planets.
“The year was 1909 and Garrett Putnam Serviss was already a respected science writer for the Hearst newspaper group.”
from the catalogue
The Colors of SpaceNovel
Marion Zimmer Bradleystandalone novel1963
Space opera, mysterious in tone, about aliens, set in far future.
“The Lhari seem peaceful and friendly, but they go to some lengths to protect their monopoly on faster-than-light travel.”
from the catalogue
Tunnel in the SkyNovel
Robert A. Heinleinstandalone novel1955
About survival and coming of age, set in far future.
“As the final test of a survivalist/explorer class, teenagers are dumped on an alien planet to use their skills while awaiting pickup.”
from the catalogue