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NASA Home News Space NOW Blog How Do We Know The Moon Landing Really Happened? How Do We Know The Moon Landing Really Happened? 15th Jun 2017 Author: Scott Davis Mankind first stepped foot on the Moon on 20 July 1969, achieving what is arguably humanity’s greatest ever feat of exploration. For two and a half hours, Neil Armstrong and Buzz Aldrin explored the lunar surface on foot while Michael Collins piloted the Apollo 11 orbiter around the Moon. That’s the history that we continue to celebrate today, 50 years on from the first landing. NASA Many of us either remember watching the landing ourselves or have heard the memories from our parents and grandparents. But what do you say when someone insists that the Moon landings never really happened? In this blog, we dig into some of the common questions around the Moon landings, and address the more curious lunar phenomena with the latest data and scientific understanding. A vast weight of evidence supports the fact that humans really did land on the Moon multiple times between 1969 and 1972. But it is important to question and think critically about events of this scale – and sometimes researching and puzzling out the answers can be half the fun! Wouldn’t the Van Allen belts have fried the astronauts? One of the most popular theories as to why the Moon landings couldn’t have happened has to do with something called the Van Allen belts. These are two huge belts of radiation that surround the Earth, shaped by the Earth’s magnetic field and pounded with high-energy particles from the Sun’s wind. It’s been claimed that humans couldn’t have passed through these belts without being fried with lethal doses of radiation. In fact, the international scientific community was aware of the Van Allen belts thanks to the Explorer, Pioneer, and Luna missions in the 1950s. Luckily, the timings of the Apollo launches were such that the Van Allen belts were at their lowest intensity, which fluctuates with the Sun’s activity. Radiation sickness occurs when you have been exposed to around 200 to 1000 ‘rads’ of radiation within a few hours. The Apollo 11 crew were within the belts for less than two hours during their journey to the Moon, and so would have only been exposed to an estimated 18 rads – well within the safe limit. There can still be some adverse effects from even this level of radiation, so NASA made sure that the Apollo 11 spacecraft was well-insulated such that the average dose of radiation over the 12-day mission was just 0.18 rads, or similar to the radiation dosage from a chest X-ray. You can work through all the maths of the estimated radiation levels, along with some helpful answers, in this NASA Education worksheet here. For more information see this excellent blog from Vintage Space. NASA /Johns Hopkins University Applied Physics Laboratory Why did the flag flap on the Moon? Another ‘giveaway’ that the landing was faked comes from the footage of the American flag that Neil Armstrong and Buzz Aldrin placed on the Moon. From photos and video, it appears to be flapping in the wind. But hold on a minute! There’s no air on the Moon so how can it flutter?! The truth is that the flag isn’t flapping. There is a horizontal rod projecting from the post at the top of the pole to hold the flag unfurled. The flag was disturbed as it was planted into the ground and kept this bent shape because of the lack of strong gravity on the Moon. In video footage of the flag being planted into the Moon’s surface, it also appears to wave back and forth. This is because when the astronauts were planting it, they rotated it back and forth to better dig into the lunar soil, which of course made the flag ripple as it swung like a pendulum- without a breeze. There’s a huge amount of footage of the flags stood on the Moon in exactly the same position. And why can’t we see stars in the pictures? Speaking of the flag photographs, it’s often pointed out that there are no stars to be seen in the background! This is actually a common feature of photographs from space, where the contrast between light and dark is extreme. The surface of the Moon reflects the strong sunlight and appears very bright in photographs. This brightness drowns out the relatively dim light from stars in the dark sky, akin to how car headlights can drown out the fainter light from nearby objects. The human eye can adjust and pick out the stars, but unless it’s set to the right settings, a camera struggles with the contrast. Astronauts on the International Space Station today regularly take photographs of the Earth that show a completely starless background, but it’s the same problem of contrasts at work. For more information, read this blog from astrophysicist Brian Koberlein or astronaut Tim Peake’s response to this question in his FAQs. NASA What about those funny shadows? Let’s talk about the shadows in photographs from the Moon. One of the subtler arguments against the Moon landings has to do with non-parallel shadows. I...