On October 7, 1959, the Soviet probe Luna 3 took the first photographs of the Moon’s far side, a hemisphere no human had ever seen since Earth’s own gravity keeps the Moon permanently facing us with the same side. Luna 3 had launched three days earlier and swung around the Moon’s south pole on October 6; the next day, as it looked back from roughly 40,000 to 42,000 miles away, its onboard camera fired off a sequence of exposures over about 40 minutes, eventually capturing 29 frames covering around 70% of the hidden hemisphere.
The camera system itself was a clever piece of Cold War-era engineering: a dual-lens unit that shot standard 35mm film, which was then automatically developed, fixed, and dried right inside the spacecraft before being scanned line by line and radioed back to Earth as a weak, static-choked video signal. Only about 17 of the 29 frames made it through cleanly when transmission finally happened around October 18, and just a handful were sharp enough to publish. Grainy as they were, the images were a sensation — they showed a far side dominated by rugged highlands with almost none of the large, dark “seas” (maria) that define the familiar face of the Moon, forcing scientists to rethink assumptions about how the two hemispheres had formed.
Luna 3 also mattered as a spacecraft in its own right: it’s considered the first successful three-axis stabilized probe, using a primitive sun-and-Moon sensor system to orient itself precisely enough to aim a camera at a target hundreds of thousands of miles away — a genuinely hard problem for 1959 hardware. The mission came just two years after Sputnik 1 and set up a string of Soviet lunar firsts that would culminate in Luna 9’s soft landing in 1966, keeping the USSR ahead in several key milestones of the early Space Race even as NASA’s Apollo program took shape.
Source: Wikipedia
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