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When it launched on May 30th, 1966,. Surveyor 1 was the US’s very first attempt to land something on another world.

The plan was for the Surveyor missions to pave the way for humans to go to the Moon. But while scientists had high hopes, most experts actually expected this little-known mission to fail. The US and others started launching flyby attempts as early as 1958, ending in mainly rocket explosions, missing the Moon, or smashing probes into the moon, although that last one was actually intentional.

So by the time NASA was ready to launch its first craft that was supposed to survive contacting the Moon’s surface, known as a soft landing, scientists estimated it had, like, a 10 to 15 percent chance of success. That craft was called Surveyor 1 and, along with its six siblings, it was commissioned by NASA a few months before. Yuri Gagarin became the first human in space.

That’s over eight years before Apollo 11 launched. Together, the six Surveyors were designed to conduct chemical analyses of the Moon’s surface and subsurface, and to take some photos, as well. Then, after Kennedy said that he wanted the US to send people to the Moon by the end of the decade, the Apollo program adopted the Surveyors as scouts, to determine if, and where, humans could safely land.

That’s because, at this point in the Space Race, scientists could only hypothesize what the Moon’s surface was like. They knew some things. They knew that the Moon’s so-called “seas” were not actually filled with liquid water, and there were a bunch of craters everywhere, but Earth telescopes weren’t advanced enough to resolve anything smaller than about half a kilometer... ...

Let alone reveal what the surface was actually made of. Except cheese. Like, obviously, some of it was cheese.

Now, some scientists argued that the Moon was hard and rugged volcanic rock. Others put forth the idea that it was powdery but firm cement. But one hypothesis stuck on scientists’ minds, that moon dust could just swallow astronauts.

Back in 1955, astronomer Thomas Gold proposed the idea that the Moon was covered in dust, created by erosion, not from wind or water, but from solar radiation and huge temperature swings between the lunar day and lunar night. So there were fears that this dust could be so deep that an entire lander would just sink right into it!. We did not know if there was actually ground to land on!

But in February of 1966, the USSR’s Luna 9 became the first craft to survive a soft landing on the Moon’s surface. Which was a good sign, but it was also significantly lighter than an Apollo lunar lander was going to be. And Luna survived its landing by bouncing and rolling around in an airbag… kind of like what NASA later did in modern days with some Martian rovers.

But that’s not something astronauts were going to do. So Surveyor 1 and its kin were a lot more analogous to future human landings, because of the weight of the craft. When it came time for Surveyor 1 to make its descent onto the Moon’s surface, it used its rocket to slow its descent until it was three point four meters up, and then it cut them off.

After a brief fall, it touched down 14 kilometers from its planned target in the Ocean of Storms. After years of planning and with the odds stacked against it,. Surveyor 1 landed safely.

The first photo Surveyor sent back was of itself while landing and it confirmed that just like Luna 9, it did not get swallowed up. So the theory from 1955 saying that the Moon has so much dust that it could swallow a spacecraft, was put to rest. Later panoramas it sent back revealed meter-sized boulders Surveyor 1 luckily missed.

And over two lunar days, which required surviving a two-week-long night, it sent back over 11,000 images. Including the first color images of lunar rocks and soil. From those images and sensors inside Surveyor, scientists finally learned about the lunar surface close up.

The surface was described as “gritty and bouldery” and “silt-like.” Most of the particles measured less than a millimeter across, but it wasn’t the dusty quicksand some feared. Based on load measurements taken during landing and the depressions made by its footpads,. Surveyor could estimate the strength and depth of the soil on the Moon’s surface and that it could hold Apollo and the astronauts.

Over the following two years, five more Surveyors were launched and four successfully landed on the Moon. Each of those carried more sophisticated equipment than Surveyor 1, revealing even more details about the stuff astronauts were going to put their boots in, like magnetic properties and chemical composition. With enough data gathered about the kind of environment Apollo astronauts would encounter, the last Surveyor was sent somewhere new.

Instead of a lunar plain near the equator, it was sent to the lunar highlands to provide a more comprehensive look at our Moon. And over a year later, scientists started sending people. There was still plenty of danger involved, but thanks to the Surveyor program, we knew a lot more about what to expect.

If you liked this underdog craft as much as we do, I have some great news for you:. We at SciShow have made a pin featuring the mini-version of this craft! It’s our SciShow Space Pin of the Month for June, and it’s available all month long at DFTBA.com/SciShow.

But it is only available in June, so make sure you order yours soon. In July, we will have a whole new pin for you. [ outro ].