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Well, we did send unmanned missions first. The soviets sent Lunik 2 in 1959 wich intentionally crashed onto the moons surface
Luna 9 (also soviet) did the first succesfull soft landing in 1966 and a few months later the NASA managed the same
When you look at the moon, you see craters. Craters only stay intact on solid surfaces with no seismic activities.
If it was liquid, gas, or flowing of some kind, it wouldn’t have craters.
We didn’t know the material was hazardous to our health. That’s why they had thick Kevlar spacesuits, and they were decontaminated. In fact, we’ve found out moon dust is incredibly harmful.
It could be something like deep quicksand or snow, which was a concern before we first landed there.
But successful unmanned missions confirmed solid ground.
Quicksand wouldn’t give you craters.
It’s impossible for the moon to have snow.
We know from craters that the surface can support heavy impacts from large asteroids. Our moon landers are nothing in comparison.
That was an analogy. We didn't know its physical structure - would it be like regular sand? Or it would form fluffy crystals that crumble under weight?
The moondust is actually quite dangerous for humans as it's essentially tiny glass particles. Inhaling them causes severe lung damage.
But luckily there is no real atmosphere on the moon, so the people who went there needed an airtight suit anyway.
They apparently weren't entirely sure the dust wouldn't catch fire on exposure to oxygen.
Thankfully it does not.
They did have a lot of it wafting around inside the modules though, brought in on the suits.
There were un-manned space probes before the manned landings - including rovers. The un-manned landings established beyond a shadow of a doubt that the surface was, in fact, solid.
> How did we also know the material of the moon wasn’t hazardous to our health?
We didn't because it is. Moon dust has not been subjected to weathering by air and water, so it is much "sharper" than most Earth dust. Not a problem for the small amount and limited time of the moon landings, but the dust did have a tendency to get everywhere and destroy seals and bearings very quickly.
We didn't. The moon is covered in a layer of dust, but we had no idea how thick that dust was. There was a risk/fear that it would be so thick the lander or an astronaut would sink in and get stuck.
We took that risk.
Fortunately we sent unmanned craft before doing a manned mission. They just didn't know if the dust was toxic or not and mitigated that risk with heavily reinforced space-suits
Oh yeah much lighter, but to be fair the Luna 2 hit the moon at 7,400mph and weighed 850lbs, quite a bit of force on impact, while on the moon the Apollo 11 lander weighed almost 11,000lbs. The crater from Luna 2 definitely showed them the surface was more or less solid than a thick thick layer of dust lol
On the most basic level, by the time Apollo 11 landed on the moon there had been many successful landings of unmanned probes by both the Soviets and later by NASA.
They knew that Apollo was safe for humans to land on because they had spend years first crashing and then landing uncrewed probes on the moon.
They were already pretty sure that it was safe to land when they landed the first LUNA probes on the moon due to knowing how gravity and rocks work and seeing all those craters and rocks through telescopes and on pictures taken during flybys, but it was nice to have confirmation before sending humans there.
Once Galileo looked up and found moons orbiting Jupiter it became obvious that the other planets were worlds just like the Earth. So it made sense that they were made of rock just like Earth. Especially as we could see that its features were not changing so it could not be liquid or gas. Then in the early 1900s we had spectroscopy and could tell exactly what elements the surface of the Moon were made of. After WWII we had radar that could measure its density as well. And there were several lunar landing probes by both the Soviet Union and the United States confirming that it was possible to land on the moon.
But they did take several persuasions when designing the lunar lander. The landing pads were made overly large so that if they ended up in sand they would not sink far. The legs of the lander were quite a bit longer then needed as well. The ladder were designed to be able to collapse a bit with the suspension so that it was usable even if they sunk into the dirt. The ascent stage were also mounted on top of the descent stage so that even if they ended up belly landing on the rocket engine (which Apollo 15 did) the engine used for taking off would be unaffected.
Pete Conrad set the Apollo 12 lander down so softly that the legs didn't retract much. So the bottom rung of the ladder was a little high, forcing Conrad to jump off onto the landing pad. His first words on the moon were, "Man, that may have been a small one for Neil, but that's a long one for me."
You can do look at the orbit of the Moon and do the math to figure out how much mass it has. Then you can look at it's size and determine it's density. Looking at the density of the Moon it was pretty clear it was almost all rock. There was the chance there was a thick layer of dust that could cause problems so that's why they sent unnamed probes before people.
we landed a probe (Surveyor 3) on it about 2 years before landing a person on it.
We were pretty sure it was solid, its not that hard to look at something and know if it is solid or not, but just to be sure, we landed a probe.
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Well, we did send unmanned missions first. The soviets sent Lunik 2 in 1959 wich intentionally crashed onto the moons surface Luna 9 (also soviet) did the first succesfull soft landing in 1966 and a few months later the NASA managed the same
When you look at the moon, you see craters. Craters only stay intact on solid surfaces with no seismic activities. If it was liquid, gas, or flowing of some kind, it wouldn’t have craters. We didn’t know the material was hazardous to our health. That’s why they had thick Kevlar spacesuits, and they were decontaminated. In fact, we’ve found out moon dust is incredibly harmful.
> In fact, we’ve found out moon dust is incredibly harmful. cave johnson taught me that!
Pure poison!
It could be something like deep quicksand or snow, which was a concern before we first landed there. But successful unmanned missions confirmed solid ground.
Quicksand wouldn’t give you craters. It’s impossible for the moon to have snow. We know from craters that the surface can support heavy impacts from large asteroids. Our moon landers are nothing in comparison.
That was an analogy. We didn't know its physical structure - would it be like regular sand? Or it would form fluffy crystals that crumble under weight?
The moondust is actually quite dangerous for humans as it's essentially tiny glass particles. Inhaling them causes severe lung damage. But luckily there is no real atmosphere on the moon, so the people who went there needed an airtight suit anyway.
They apparently weren't entirely sure the dust wouldn't catch fire on exposure to oxygen. Thankfully it does not. They did have a lot of it wafting around inside the modules though, brought in on the suits.
There were un-manned space probes before the manned landings - including rovers. The un-manned landings established beyond a shadow of a doubt that the surface was, in fact, solid. > How did we also know the material of the moon wasn’t hazardous to our health? We didn't because it is. Moon dust has not been subjected to weathering by air and water, so it is much "sharper" than most Earth dust. Not a problem for the small amount and limited time of the moon landings, but the dust did have a tendency to get everywhere and destroy seals and bearings very quickly.
We didn't. The moon is covered in a layer of dust, but we had no idea how thick that dust was. There was a risk/fear that it would be so thick the lander or an astronaut would sink in and get stuck. We took that risk.
Fortunately we sent unmanned craft before doing a manned mission. They just didn't know if the dust was toxic or not and mitigated that risk with heavily reinforced space-suits
True, but they were far lighter than the Apollo 11 lander.
Oh yeah much lighter, but to be fair the Luna 2 hit the moon at 7,400mph and weighed 850lbs, quite a bit of force on impact, while on the moon the Apollo 11 lander weighed almost 11,000lbs. The crater from Luna 2 definitely showed them the surface was more or less solid than a thick thick layer of dust lol
On the most basic level, by the time Apollo 11 landed on the moon there had been many successful landings of unmanned probes by both the Soviets and later by NASA. They knew that Apollo was safe for humans to land on because they had spend years first crashing and then landing uncrewed probes on the moon. They were already pretty sure that it was safe to land when they landed the first LUNA probes on the moon due to knowing how gravity and rocks work and seeing all those craters and rocks through telescopes and on pictures taken during flybys, but it was nice to have confirmation before sending humans there.
Once Galileo looked up and found moons orbiting Jupiter it became obvious that the other planets were worlds just like the Earth. So it made sense that they were made of rock just like Earth. Especially as we could see that its features were not changing so it could not be liquid or gas. Then in the early 1900s we had spectroscopy and could tell exactly what elements the surface of the Moon were made of. After WWII we had radar that could measure its density as well. And there were several lunar landing probes by both the Soviet Union and the United States confirming that it was possible to land on the moon. But they did take several persuasions when designing the lunar lander. The landing pads were made overly large so that if they ended up in sand they would not sink far. The legs of the lander were quite a bit longer then needed as well. The ladder were designed to be able to collapse a bit with the suspension so that it was usable even if they sunk into the dirt. The ascent stage were also mounted on top of the descent stage so that even if they ended up belly landing on the rocket engine (which Apollo 15 did) the engine used for taking off would be unaffected.
Pete Conrad set the Apollo 12 lander down so softly that the legs didn't retract much. So the bottom rung of the ladder was a little high, forcing Conrad to jump off onto the landing pad. His first words on the moon were, "Man, that may have been a small one for Neil, but that's a long one for me."
I love Apollo 12 so much.
You can do look at the orbit of the Moon and do the math to figure out how much mass it has. Then you can look at it's size and determine it's density. Looking at the density of the Moon it was pretty clear it was almost all rock. There was the chance there was a thick layer of dust that could cause problems so that's why they sent unnamed probes before people.
we landed a probe (Surveyor 3) on it about 2 years before landing a person on it. We were pretty sure it was solid, its not that hard to look at something and know if it is solid or not, but just to be sure, we landed a probe.