A witchcraft invocation within a book within a dream — nested speculation.

Journey to the Moon seen through "Demon's" eyes.

Somnium manuscript leaked: Kepler’s mother accused of witchcraft.

Scientifically valid insights (Lagrange points, eclipses from Moon perspective, Privolva / Subvolva, planet size variation, size of the Moon)

Somnium translates Kepler’s Three Laws (Elliptical orbits, Equal areas in equal times, Harmonic Law) into narrative form