The Man In The Moone

In 1638, in the first age of modern astronomy, as the starts opened up to us, the scientists of the time found themselves bound into fantastical visions based on their new knowledge. 

This was perhaps the first 'hard' sci fi, at least based on the cutting edge of knowledge from the time.

Drawing on contemporary theories of Copernicus, Kepler, Galileo, and Gilbert, the inhabitants of the Moon in this story are a tall Christian people encountered by a roguish hero who must learn of their lands, and gains items that allow the control of light, heat, and gravity. Described by Edgar Allen Poe as “a singular and somewhat ingenious little book”, it was a direct influence on Jules Verne and HG Wells.