As the very first close-up image of another planet beamed to Earth on July 15, 1965, the engineers at NASA's Jet Propulsion Laboratory couldn't wait to see it.
This was Mariner 4, the first spacecraft to photograph the surface of Mars. At the time, it was the farthest any human-made object had ever traveled.
But the computers were going to take eight hours to process a single image before the excited scientists could get a glimpse.
So engineer Richard Grumm had the idea that they should print out the data as it came in from a tape recorder receiving the signal from the spacecraft - and the engineers colored the first image by hand. Dan Goods, a visual strategist at JPL, retold this incredible story on his blog, Directed Play.
Here's how it happened: