Moon

The is a planetary body orbiting the Earth. It was created a millennium ago by Hagoromo Ōtsutsuki, the Sage of the Six Paths.

History
Different accounts have been given as to how the Moon was formed. In early versions of the story given in the series, Hagoromo is said to have created the Moon at the end of his life, using it to store the Demonic Statue of the Outer Path so that the Ten-Tails could never be reborn. According to later versions, the Moon was created by Hagoromo and his brother, Hamura, when they defeated their mother, Kaguya, with Six Paths — Chibaku Tensei. After the moon's creation, Hamura took leadership of the Ōtsutsuki clan and settled on the Moon in order to guard the Demonic Statue.

Centuries later, sometime prior to the Second Shinobi World War, Madara Uchiha summoned the Demonic Statue from the Moon with his Rinnegan, intent on using it to bring peace to the world. In order to achieve this goal, Madara came up with the Eye of the Moon Plan, wherein the Ten-Tails would be revived and its jinchūriki would cast the Infinite Tsukuyomi on the Moon, thereby ending all conflicts by trapping the world in a perpetual dream. Fulfillment of much of the plan ultimately falls to Obito Uchiha upon Madara's death, though Madara is revived in time to see the plan completed during the Fourth Shinobi World War. The Infinite Tsukuyomi is later broken by the combined efforts of Naruto Uzumaki and Sasuke Uchiha.

In The Last: Naruto the Movie, Hagoromo asked Hamura to monitor mankind, a task that was passed to the rest of the Ōtsutsuki when Hamura died. Over the centuries the Ōtsutsuki's numbers declined and Hamura's mission became corrupted: if mankind was deemed unworthy, they were to be destroyed. A millennium after they settled the Moon, the last surviving Ōtsutsuki, Toneri, begins moving the Moon towards the Earth so that he can destroy it and rebuild a purer world from the ashes. As the Moon begins breaking up in the Earth's gravity and increasingly rains meteors upon its surface, Konohagakure sends a team to the Moon to stop the imminent collision. Toneri is eventually defeated by Naruto Uzumaki and Hamura's actual mission is afterwards explained to him by Hinata Hyūga. Apologetic, Toneri restores the Moon to its previous orbit and, despite an invitation to live on the Earth, stays on the Moon, vowing that it will never threaten the world again.

Environment
The exterior of the Moon is barren, covered with craters and canyons. It has a weak gravity, but is still able to maintain a breathable atmosphere. Despite its harsh conditions, the Ōtsutsuki were able to settle on the Moon due to their unique anatomy and physiology. To improve its habitability and allow their population to thrive, the Ōtsutsuki built the Tenseigan at the center of the Moon, granting them light, powering their equipment, and allowing them to control the Moon's movements. Similar to a Dyson sphere, they created a vast environment on the Moon's interior surface, complete with oceans, mountains, forests, and various animal species, however this environment was far smaller than the full size of the moon itself. Several villages were built across the landscape, which were steadily abandoned as the Ōtsutsuki's population dwindled.

The artificial sun at the center of the Moon created by the Tenseigan is actually a barrier, within which are housed various important sites, such as Hamura's shrine, the Tenseigan itself, and a castle where Toneri lives. All are guarded by an army of puppets, controllable without chakra threads because of the Tenseigan, as well as the Statue of the Ōtsutsuki Clan.

There is at least one portal that enables travel from the Earth to the Moon and back. Located underground, the portal itself takes the form of a spring of green water, though contact with the water doesn't leave one wet. By entering the portal, one travels through a dimension filled with various orbs, some of which are earthen in composition, others trap those who contact them in their own memories. At the Moon's end of the portal is the Gatekeeper, a giant crab that prevents unauthorized access. This portal collapses shortly after Toneri's defeat.

Trivia

 * The anime often depicts the moon as red during significant events.
 * There have been cases that both the tailed beasts and their jinchūriki are affected to a certain degree during a full moon:
 * According to Gaara, Shukaku's blood-lust is especially strong during a full moon.
 * In the anime, Blue B, during his time as Gyūki's jinchūriki, noted that he would have trouble sleeping during the nights of the full moon, because anytime he would stare at it, it would reflect the loneliness in his heart. Gyūki would take advantage of those moments of weakness and try to control over Blue B's body. Blue B was also shown to take sleeping pills to help with this side-effect.