Many people consider Apollo 15 to be the crowning glory of the Apollo programme in terms of science. It's therefore quite fitting that the crew managed to find time to pay homage to one of the most famous scientists of all time.
Although Apollo 9 did not travel to the Moon, it still had a very important role to play in the lead up to the first lunar landing. Here are 10 reasons why it deserves more recognition.
Neil Armstrong and Dave Scott made the first ever docking in space look easy. However, just a few minutes later and out of radio contact with Mission Control, they experienced NASA's first near-disaster in space.