Mariner 4

If everything’s working as planned, a NASA spacecraft is rapidly closing in on one of the worlds of the solar system: Pluto. New Horizons is set to speed past the icy world tomorrow. That’s the 50th anniversary of the first encounter with another icy world: the planet Mars.
AUDIO: July 14th: Encounter Day. 15,000 miles from Mars now. 22 minutes until the first picture...
And as this NASA documentary suggests, just like now it was a time of high excitement. Mariner 4 was scheduled to fly past Mars, snapping pictures of the Red Planet along the way. And just what it would see was anyone’s guess. Scientists had ruled out the possibility of canals on Mars — the remnants of an ancient civilization — but some expected to see a world that in some ways resembled Earth.
AUDIO: The camera sensor now sees the planet Mars.
Mariner 4 was the second of a pair of Mars-bound spacecraft. Its twin, Mariner 3, failed at launch. But Mariner 4 was right on target.
On July 14th, 1965, it recorded 22 picture