People have invented a number of myths about the moon over the years. But Apollo 11's historic trip to the lunar surface in 1969 helped to debunk many of them, as it deepened humanity's understanding of Earth's natural satellite.
Take a look at how Apollo 11 helped to dispel several familiar and interesting myths about the moon:
Myth 1: The moon is made of green cheese The idea that the moon is made of green cheese originated from fables in which the reflection of the moon in a pool of water was mistaken for a wheel of cheese. Though scientists never considered the moon a dairy product, the idea permeated popular culture. [Apollo 11 Moon Landing 45th Anniversary: Complete Coverage]
Apollo 11, along with the lunar exploration that prepared for it, put the idea to rest with its studies of the composition of the moon. In addition to examinations of the surface by satellites, Apollo 11 and other missions returned a total of 842 lbs. (382 kilograms) of moon rocks that were clearly inedible.
Although science had ruled out the possibility that the surface of the moon could be green cheese long before the Apollo 11 mission, the lunar landscape remained mysterious. Craters from meteorite strikes suggested that the landscape contained dust, but the thickness of the dust remained uncertain. Some scientists suggested that the finely powdered dust could swallow up spacecraft that landed on the surface. The successful landings of five robotic NASA Surveyor craft in the late 1960s revealed that such worries were unwarranted.
Myth 2: There are moon bunnies on the lunar surface Many cultures studied the light and dark regions of the moon, and surmised that the darker areas formed what looked like a giant rabbit. From Asia to South America, the folklore abounds about how, in various ways, a rabbit's image had been imprinted on the lunar surface. Other myths discuss the presence of rabbits on the moon. [The Moon: 10 Surprising Lunar Facts]
Shortly before Apollo 11 reached the moon in 1969, the following conversation took place between mission control in Houston and Michael Collins, the astronaut who remained in the lunar orbiter while Neil Armstrong and Buzz Aldrin explored the moon's surface.
Houston: Among the large headlines concerning Apollo this morning, there's one asking that you watch for a lovely girl with a big rabbit. An ancient legend says a beautiful Chinese girl called Chango-o has been living there for 4,000 years. It seems she was banished to the moon because she stole the pill of immortality from her husband. You might also look for her companion, a large Chinese rabbit, who is easy to spot since he is always standing on his hind feet in the shade of a cinnamon tree. The name of the rabbit is not reported.
Michael Collins: OK. We'll keep a close eye out for the bunny girl.
Needless to say, the astronauts didn't find any rabbits, or lovely banished women, on the lunar surface.
Myth 3: The moon has a dark side The moon's rotation syncs with the Earth in such a way that the same face is always pointed toward the planet. As a result, nearly 40 percent of the lunar surface remains unseen by most human eyes, leading many people to refer to the back of the moon as its "dark side". However, when the moon shines during the day, its unseen or far side points toward the sun, bathing it in light.
The first people to observe the far side of the moon with their own eyes were Apollo 8 astronauts Frank Borman, Jim Lovell and Bill Anders. After the famous moonwalk, Apollo 11 astronauts rejoined the orbiting Columbia and passed behind the moon on their journey home.
Myth 4: The moon's distance from Earth is set Though the moon is a familiar object in the sky, its distance from Earth is constantly in flux. When Neil Armstrong and Buzz Aldrin landed on the moon, they set up the lunar ranging experiment, which remains in place today. The astronauts set up a lunar laser ranging reflector, a mirror designed to reflect pulses of lasers fired from Earth. Three more mirrors have since been left on the moon for similar purposes, set by astronauts from Apollo 14 and 15 and one French-built reflector placed by the unmanned Soviet Lunokhod 2 rover.
Here's how the laser ranging reflector works: Scientists on Earth send a laser beam through an optical telescope to hit the reflectors. By measuring how long it takes the beam to travel through space to the moon and back, they can calculate the distance to the moon with an accuracy of better than one part per 10 billion. That's equivalent to determining the distance between Los Angeles and New York to a precision of one hundredth of an inch.
As a result, scientists have determined that the moon is spiraling away from the Earth at a rate of 1.5 inches (3.8 centimeters) per year. [The Apollo Moon Landings: How They Worked (Infographic)]