I lived through it, and through the scientific discoveries and surprises, and watching the take off and splashdown and watching them live for hours on the Moon. I don't for a moment doubt it really happened.

But for those who need reasons: I think the clearest evidence is from the rocks themselves.

You can watch a video of an astronaut pick up a rock on the Moon, then go and look at the detailed scientific study of that rock here on Earth.

Scientists still use those rocks collected in the 1960s and 70s to answer questions that weren't asked back then using instruments that weren't yet invented to measure things they couldn't measure back then.

Also, the rocks are riddled with micrometeorite impact mini craters which you can only see with an electron microscope.

Spherule with micrometeorite damage in lunar rocks.

They couldn't simulate these back then. Even to this day we can't do it.

As an example of how different lunar rocks are - if you heat genuine lunar regolith (crumbly “soil”) in a microwave, it turns into glass in 30 seconds because of all the micrometeorite glass in it and because that glass is intimately mixed up with nanophase iron created in processes on the lunar surface which amplifies the effects of microwaves.

That doesn't work with the regolith simulants they make on Earth so some things can only be answered by using the genuine lunar regolith - and the only source for that is from the Apollo missions.

The few meteorites we get from the Moon aren't the same thing at all. And back at the time of Apollo then the meteorites from the Moon in Antarctica hadn't yet been discovered.

Here are answers to some of the things brought up by conspiracy theorists

• Van Allen belts - they went through the least intense part of the belt, and they spent only a short time in them. The total dose from the Van Allen belts for their mission was less than their dose for cosmic radiation. They did have some protection from the spacecraft. They are deadly if you spend days in them. But we regularly send spacecraft with sensitive electronics through the Van Allen belt no trouble at all. You wouldn't put a satellite up though to orbit within them. That's why most satellites are either in LEO (below the belts) or GEO (well above them) or in carefully chosen orbits in between.
• Waving flag - you can see if you watch the video that it started moving as a result of the astronauts touching it as they struggled for some time to insert the pole into the lunar soil. On the Moon as on Earth if you set something moving back and forth it continues for quite a while before it settles down. It had a rod through the top to hold it up.
• Not seeing the stars - that's easy, if you have ever tried taking a photograph at night, you probably know that if there are bright lights in the photo, usually you don't see the stars at the same time. It's just an exposure setting thing. Long exposure and you see the stars but the brighter areas are washed out. Short exposure and you see bright things clearly but no stars. They were photographing the lunar landscape in full sunlight so had to use a very short exposure, so no stars visible.
• There were several tragedies yes, especially the Apollo 1 fire. At that time they used oxygen for the atmosphere in the capsule. They thought it was safer, to leave out the nitrogen which can cause problems, not realizing quite how much of a fire risk it was and didn't do fire risk tests. The Russians had tragedies too. Just last year then Virgin Galactic had a tragedy with one of their test pilots dying in a test. Two space shuttles crashed. Going to space at present is risky, that's all there is to it. Our best spacecraft is the Soyuz, for humans and there have been no crashes of that for a long time, and it has multiply redundant safety systems - most would say it is very safe for a spacecraft. Still, it's nowhere near as safe as flying in an airplane or traveling in a car.
• We do have colour movie footage of the Apollo 11 landing. This shows both at once. The live transmission was in black and white because the technology they had wasn't up to the task of transmitting in colour. It also incidentally shows them struggling to get the flag planted, and you can see how it waves about after that because of their struggles
• With the video of the take off, question of how they can keep it trained on the lunar ascent module with the 2.7 seconds delay - they knew exactly what the spacecraft was going to do so could anticipate this and move the camera to where they knew it would be even though they could only see it 2.7 seconds after sending the signal to move the camera.
• Why didn’t they shine a light back towards Earth to show that they were there? - It's not possible to set up a bright light on the Moon bright enough to be seen from Earth with the technology they had then, short of setting off a nuclear explosion - a nuclear explosion would be bright, for a couple of seconds it would be as bright as an 8% moon, but even that would not be that easy to see given that they were on the bright section of the Moon. Anyway it's forbidden by the Outer Space Treaty. People tend to forget how far away the Moon is. If Chicago was on the Moon, its street lights would shine as about an 11th magnitude star. We can only see down to 6th magnitude (maybe 7th) with naked eye. You'd need a good telescope just to see the lights of Chicago when it’s locally the lunar night on the Moon.
  
  The astronauts were on the lit up portion of the Moon. I can't think of anything they could have done with the technology back then that would fit in the Apollo module and be visible from Earth. It would be hard to do anything we’d notice even with modern technology, possibly lots of high power portable lasers pointed at Earth? Even then it would be tricky to do and hard to spot. You might like to see my Could You See Moon City Lights Or A Greenhouse From Earth? Just For Fun
• They did however leave retroreflectors on the Moon and we can use those to this day, shine a laser at the Moon and they reflect the light back exactly along the path so you can detect the photons reflected off the Moon. It's a very weak signal by the time it gets back to Earth, you can't see it, but you can measure it.
• Why couldn’t they jump higher? - the spacesuits were very clumsy and they didn't want to damage them either, which is why they didn’t engage in athletics. I don't know how high they could have jumped but they weren't engaged in an athletics competition. Try doing a standing jump yourself - if you aren't an athlete probably you won't get nearly as high as the astronauts did.
• Those glints in the video of the astronauts I think show light glinting off the radio antenna attached to their backpacks.
• It's no wonder Buzz Aldrin punched that moon hoax conspiracy theorist who kept asking him to swear on the Bible that he went to the Moon. He'd been pestered by that chap over and over. Anyway apart from a reasonably natural human reaction of someone like him in a situation like that, I think that if he'd acceded to the request it would have made things much worse, the conspiracy theorists would then probably have just gone on and accused him of lying while swearing on the Bible which for some Christians would make it much worse, there is no way it would have lead to conviction. Can you imagine that chap saying to Buzz Aldrin: "Right thanks for swearing on the Bible, now I believe you"? Of course he wouldn't have done that. It's a "catch 22" situation with no right response.

There's much more, the photographs of the lunar landing sites by LRO

Also photos by the Indian orbiter (independent therefore of NASA) and Japanese orbiter that show the dust thrown up by the landing.

https://web.archive.org/web/2010....

Also many who tracked them via radio through the mission.

Including an enthusiastic amateur radio astronomer who aimed a powerful radio antenna at the Moon and recorded the transmissions from the astronauts on the surface - which he only heard when the antenna was pointed directly at the Moon.

And anyway we didn’t have the video and film making technology back then to hoax it, see:

See also, my answer to What are the best arguments for debunking Moon Landing Hoax Conspiracy Theories? and other answers there What are the best arguments for debunking Moon Landing Hoax Conspiracy Theories?

I think that to get caught up in these conspiracy ideas deflects attention away from the real issues. Which are things we can do something about. Things like health care, climate change, human rights, even asteroid impact detection and prevention for that matter, real issues that can be addressed.

For asteroids see my Giant Asteroid Headed Your Way? - How We Can Detect And Deflect Them - with a space telescope costing half a billion dollars we could find most of the potentially hazardous asteroids down to 40 meters diameter in six and a half years. The astronomers are doing so much to detect asteroids but could do so much more with this level of funding.