In his book, A Universal Natural History and Theory of the Heavens, Immanuel Kant suggested the structure of the Milky Way and the existence of other galaxies. Credit: Linda Hall Library
Though often recognized as a philosopher, Immanuel Kant (born April 22, 1724) made several contributions to early theories of cosmic organization. Surveying the band of stars that appear across our sky – the Milky Way – Kant concluded that our galaxy must be a wide, rotating disk. He published this conclusion in A Universal Natural History and Theory of the Heavens (1755). In the same book, he was the first to suggest that the nebulae visible from Earth were actually other galaxies, putting him well over a century ahead of Edwin Hubble’s confirmation of this structure. Kant also contributed to our concepts of tidal locking, gravity, cosmic evolution, and more.
