Making the unknown known

Cosmos, the book by Carl Sagan, does something remarkable. It starts in a distant part of the universe. It does a slow zoom, through desolate space, through groups of galaxies, through the Milky Way, through a remote arm of the Milky Way, through the solar system, past the most distant plants, finally into Earth. It shows us as a tiny note of dust in an obscure part of the universe. Then, it moves…