According to NASA, the boldest test flight ever is not the Wright Brothers at Kitty Hawk, Chuck Yeager's breaking of the sound barrier, or even Yuri Gagarin becoming the first human in space. They argue it is actually the first flight of the Space Shuttle, which is marking its 40th anniversary in April 2021.
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.
Alan Shepard's road to the Moon was not a straightforward one, so you can't blame him for wanting to have a little fun on the lunar surface. He joked in later life that he was probably better known as 'the astronaut who played golf on the Moon' than he was as the first American in space.
Nicknamed 'the Brain', Ed Mitchell was the second ever astronaut to have a PhD. On his way to and from the Moon in 1971, he took part in a psychic experiment designed to see if it was possible to transmit and receive thoughts across tens of thousands of miles.
Gemini 6A is best known for achieving the first ever rendezvous in space, a key stepping stone in the journey to the Moon. That wasn't the only 'first' it achieved, though.