It was 44 years ago, on July 2oth/21st, 1969, that two men — Neil Armstrong and Buzz Aldrin — made history by becoming the first two humans to set foot on the Moon. Regardless of the excitement and fervor that accomplishment caused at the time, in the years since there have been plenty of people who have tried to cast doubt over the achievement, and they've used various arguments to support their claim that it was all a hoax.

#1: The astronauts would have died from radiation exposure

This is probably the most common 'Moon hoax' claim that I've seen: The astronauts would not have been able to survive the trip because they would receive a lethal dose of radiation, both from passing through the Van Allen radiation belts, and from being beyond Earth's magnetic field and on the Moon's surface.

The truth is, for their entire trip to the Moon and back, the astronauts only received a dose equal to around one-tenth of one per cent of the radiation needed for a lethal dose (their total exposure was roughly 11 millisieverts and a lethal dose is at 8,000 millisieverts).

The reason for this is that the harmful effects from radiation are based on strength of the radiation and the time of exposure. You'd need to spend nearly 4 months inside the Van Allen belts to accumulate a lethal dose. The astronauts passed through them in roughly one hour. As for their time spent beyond Earth's magnetic field, where they were exposed to cosmic radiation, as I discussed back at the end of May, an astronaut could make a 1-way trip to Mars and not receive a dose that exceeds NASA's lifetime limits (and those don't even come close to lethal levels).

#2: You can't see the stars in photos of the Moon

Here on Earth, when there's a black sky, we see stars. The photos taken on the Moon show the astronauts, lander and terrain with a black sky, but no stars. So, they must have been filming on a sound-stage and just used a black backdrop.

The reason you can't see the stars in photos of the astronauts on the Moon isn't because the stars aren't there, it's because of the exposure limits of cameras.

When the astronauts were out taking pictures, it was full daylight on their side of the Moon. There's only an extremely thin atmosphere on the moon — not enough to block out the stars during the day — so the sky still appears black. It also means that the sunlight is very strong at the Moon's surface. If the astronauts aimed a camera at the sky and let it sit there and take a long-exposure picture, you would, indeed, see the stars. However, with astronauts' taking pictures of each other, in their bright white suits (designed to reflect as much sunlight as possible to keep the suits from overheating), the camera couldn't get a good, crisp picture of the astronaut and still have the right exposure to pick up the much fainter stars in the background. Even taking pictures of the surrounding lunar landscape would have too much reflection from the surface to let the camera get a good exposure on both the landscape and the stars.

#3: Astronauts can be clearly seen even though they should be in shadow

There's a famous picture of Buzz Aldrin on the surface of the Moon, where he's casting his shadow in front of him. With the Sun behind him, some think that the entire front of his spacesuit should have been in shadow, so it's clear to them that there's a second light source, and thus they weren't really on the Moon when the photo was taken.

However, this has to do with how bright the sunlight is and how reflective the surface of the Moon is. The Sun is, indeed, behind Aldrin, but there's so much light being reflected from the bright surface of the lunar landscape that it's still fully illuminating the front of Aldrin's suit.

Story continues