- 7 December 1972 – The Blue Marble photograph is taken by the Apollo 17 crew
- 8 December 1992 – Galileo completes the second Earth flyby
- 14 December 1962 – Mariner 2 becomes the first space probe to perform a flyby of a planet, when it passes within 35,000 kilometers of Venus
- 17 December 1917 – 2001: A Space Odyssey science fiction author Arthur C. Clarke is born
- 19 December 2013 – Gaia is launched for the mission to study billions of stars in the Milky Way
- 21 December 1968 – Apollo 8, is launched with the first crewed spacecraft to leave Earth orbit, reach the Moon, orbit it, and return safely to Earth
- 27 December 1571 – Astronomer, mathematician, and astrologer Johannes Kepler is born
