Moon

The moon is a celestial body that appears during the Minecraft night.

Nighttime
Nighttime begins after the sun fully sets over the western horizon, and the moon rises over the eastern horizon. As time passes, the moon will slowly move over the sky toward the western horizon. Overall, nighttime lasts about 7 minutes (in real time). Players can track the moon's position in the sky using a clock.

During the night, the moon illuminates the surface in the same manner as the sun; however, light levels will fall to a minimum of four. This allows hostile mobs such as zombies and creepers to spawn. To prevent that you can swap the difficulty to peaceful, or turn off Day-night cycle.

Grass blocks and saplings will not grow in moonlight, nor will they decay. To grow them at night requires the use of light sources such as torches. On the other hand, crops will continue to grow.

Nighttime can be skipped entirely using a bed, provided there are no monsters nearby.

Stars
Together with the moon, the night sky also consists of stars. Stars appear as bright points, and the starfield rotates with the moon as the night progresses. Because they rise in the east and descend in the west like all celestial bodies, you may navigate by the stars even when the moon is not visible.

Phases
The Moon goes through eight lunar phases, and changes phase every night. This allows the player to keep rough track of the passage of time, even after spending a few game days underground.



The phases are (in chronological order as they appear in game):


 * Full Moon
 * Waning Gibbous
 * Last Quarter
 * Waning Crescent
 * New Moon
 * Waxing Crescent
 * First Quarter
 * Waxing Gibbous

There is no explicit command to change the moon's phase, but using will advance it to the next phase. Using will advance it to the previous phase (of the next lunar cycle).

Effects on mobs


The moon and its different phases have two subtle effects on mob spawning. For instance, the numbers of slimes that spawn in swamps are proportional to the moon's fullness; they are most numerous during the full moon, but none will spawn during the new moon. This does not influence the spawning of slimes in designated chunks below an altitude of y=40.

The moon's phase will also affect the chances of certain monster buffs taking effect. On a fuller moon, skeletons and zombies have a higher chance to be able to pick up items, and to spawn with weapons and armor. Furthermore, there is a higher chance for their equipment to be enchanted, and if it is, the enchantment levels will be higher. A fuller moon phase will also give spiders a higher chance to spawn with random beneficial status effects, including invisibility. All of these effects combine with the world's set difficulty, with higher difficulty giving a greater chance for mob buffs.

Trivia

 * One Minecraft lunar cycle (from full moon to full moon) takes 2 hours 40 minutes of play time. This means there are approximately 9 lunar cycles in one real-world day (24 hours) of play.
 * Whereas the moon moves independent of other celestial bodies in real life, the Minecraft moon is fixed in the sky relative to the stars.
 * Thus, solar eclipses are currently impossible in Minecraft.
 * Standing or flying at a height above the terrain of approximately 1.4x the render distance, the sun will appear opposite to the moon in the sky, making it seem almost as if the player is in space.
 * The moon appears to be lit from a source in the north or south, whereas it "should" be lit from the east or west (by the sun).
 * For that matter, being fixed opposite to the sun, it should be constantly full and should result in a total lunar eclipse every night at midnight.
 * The star pattern is based on a seed, but not your world's current seed. Like the bedrock pattern the stars are always based on the same one seed (number unknown). According to Mojang this is to prevent people on multi-player from working the seed out from reading the star pattern.
 * The eight lunar phases actually move backwards in sequence. They go from New Moon, then Waning Crescent, the 3rd/Last Quarter, then Waning Gibbous, then Full Moon, and so on. (Note that the gallery has them in the correct order)