Moon

A moon is a natural satellite orbiting a planet. The Earth's only moon is known rather unimaginatively as "the Moon" (or sometimes "Luna" if you're feeling fancy, like science fiction, or speak Spanish or Latin). Being the most noticeable object in the night sky, if it is even out that is, it is a subject of much woo, particularly in astrology, where it is usually given a female quality and a high degree of importance in the sky.

Physical properties
The Moon is one of the largest natural satellites of the Solar System with a diameter of almost 3,500 kilometers, but even with that size it has just 1/81 of the Earth's mass due to a much lower mean density than our planet given that it's composed of a much larger percentage of rock than the latter. It has very little atmosphere.

As even a casual glance with binoculars can show, the Moon is pockmarked with a whole lot of craters caused by asteroid and comet impacts of all sizes from tiny microscopic ones found on lunar rocks brought by the "Apollo" missions to large, multi-ringed basins with diameters of up to, and like the smaller craters in better or worse state of conservation with the being the best preserved one and showing very nicely such several rings of massifs and scarps in contrast to     ones only discovered through detailed study. The crater-saturated areas that are visually pale are known as "terrae", while the large, dark, areas that form the "Man in the Moon" are known as "maria" (latin for "seas"), as they were thought centuries ago to be filled with water, but are currently known to be plains of solidified lava that covered previous crater-filled areas back in the young days of the Moon.

As the first two images that illustrate this article show, the lunar far side, entirely unobservable from Earth except when allow us to see a small part of it, has a very remarkable paucity of "seas," which has been attributed to a thicker crust inhibiting lava from oozing to the surface. The lack of maria as well as very little erosion, as the Moon has a very thin atmosphere, no water, and few if any current geological activity, shows how severely it (as well as other planets and moons) was whacked during the formation of the Solar System, and how such cratering has been especially on its backside far side the main sculptor of the lunar surface. Note that the far side is not dark as is often thought, as the Sun shines there as much as on the near side; the only difference is the lack of Earth hanging upon the moonscape, and "dark" is both in the sense of being unknown until spacecraft charted it and that communications with spaceships there are blocked by those thousands of kilometers of Moon rock unless a relay satellite is used, as the Chinese did with their lander and the.

Creationism
Creationists argue that the moon proves young Earth. In a word, no.

The Moon has been a source of astronomical study for at least three millennia. To say that science has failed to explain key elements of lunar motion, geography, or composition is to be willfully blind. Nonetheless, many creationists fabricate "errors" in scientific studies of the Moon and suggest that since science has failed, the only alternative is (their particular brand of) creationism. This is gap-filling with God to an absurd degree. Assuming, for once, that science could not explain the Moon, this does not imply that the only explanation is God. Science evolves. Not everything is known now, nor should science be forced to prove everything in the universe to disprove creationism. The standard for evaluating creationist claims about scientific disciplines is the same that applies to all scientific theories: does the claim match the evidence? Regarding creationism, the answer is of course a resounding "no".

Creationist claims surrounding the moon:


 * Lunar recession (the moon is going away from the Earth too fast)
 * Lunar dust (there's not enough moon dust)
 * Lunar formation (the moon couldn't have formed)
 * Lunar radioactivity (the moon is too hot)
 * Atmosphere of the Moon (there's too much moon gas)
 * Lunar bukkake hypothesis (the moon got shot with water during the Flood)

Moon landings and the idiots that claim they are a hoax
Twelve American astronauts landed on the Moon between 1969 and 1972, took pictures, left behind some junk, and came back home with some rocks. Deal with it.

The moon gives off light
It seems natural enough for pre-scientific cultures to assume that the sun and the moon both give off light. However, this is not true; the moon is a reflector of light, not a generator, save as a black body, and in that sense, everything gives off light. A good example of this is Genesis 1:16, in which god creates "a greater light to rule the day" (the sun) and "a lesser light to rule the night" (the moon). So there goes any claim that Genesis is scientific. Even so, the moon can appear during the day and not in the night at all depending on what phase it is currently in, so it doesn't necessarily rule the night either.

Bill Nye the Science Guy took the bible to task on this one. It wasn't popular.

The moon's light is also not actually bluish or silvery, but is perceived such way due to the

Muhammad: Moon-Smasher
According to the Qur'an, Muhammad broke the Moon. Yes, really. This is a real piece of silliness that basically renders any claim that the Qur'an is science to be utter bullshit. It's total fantasy.

Nevertheless, some truly dedicated followers of the "TEH QUR'AN IS TOTES SCIENCE" argument have still tried to prove it. A few of them stoop to using an article proposing that NASA found a crack that ran all the way around the Moon; this argument is a total fraud, as anyone with a non-Qur'an-addled brain can spot.

Many Islamic scholars believe that this verse is best understood as a statement of something to occur at the final judgment. This is supported by the fact that the Surah concerns itself with that judgement, the references to previous judgements are in the middle part of the Surah, and also that the immediate context of the verse makes a future rather than past interpretation more likely. While there is weak support in the Sunnah for a literal past tense interpretation of the event, even in that case, a plausible interpretation would include the possibility of e.g. a large asteroid impact providing the appearance of the Moon splitting (contemporary writings from India record one such event). The writing here is poetic, so what exactly "the Moon is cleft asunder" indicates is uncertain, and based on the Arabic, is just as likely to have a metaphorical meaning. In other words, there is no single interpretation of what exactly this verse refers to. If taken literally, it refers to some obvious sign in the moon, figuratively it would likely refer to Islam "tearing assunder" the religious fabric of the Middle East (if past tense) or the world (if end times was meant).

Other Muslim apologetics claim that when Muhammad put the Moon back together, there was no crack because it was joined together perfectly, molecule-to-molecule. This is special pleading on a grand scale and should be ignored.

Apparent size and the idiots that claim Aliensdidit
It is a fact that the geometry of the Earth-Moon-Sun system is such that the apparent sizes of the Sun and the Moon, as seen from Earth, are very close to the same. During a total solar eclipse, it is often the case that the Moon sits right on top of the Sun like two stacked pennies. (This is not always the case, however; sometimes the Moon is at apogee and an annular eclipse is the result. Like a US quarter (24.26mm) stacked on a UK 2p (25.9mm).)

Astronomers tend to just accept this as a fact of nature. Pseudoastronomers, when lecturing to, say, MUFON interest groups, are likely to cue up the Powerpoint™ slide and say "Can this be coincidence? I THINK NOT!" The extremist pseudoastronomical position is that the Moon is obviously artificial, towed carefully into place by Aliens.

Hollow Moon
For some cranks, the Moon is hollow and some sort of spacecraft built by the Galactic Empire.

Moon cheese!
The moon is quite definitely made of cheese. Wallace and Gromit proved it.

Life on the Moon
Back in 1835, the New York newspaper The Sun published a series of articles, claiming the British astronomer had seen goats, unicorns, Batman man-bats, and more in the Moon with a state-of-the-art telescope. Of course, it turned out to be a hoax to boost the newspaper's sales.