Moon rabbit

The Moon rabbit, also called the Jade Rabbit, is a rabbit that lives on the moon in East Asian folklore. The legends about the moon rabbit are based on the traditional pareidolia that identifies the markings of the moon as a rabbit pounding in a mortar. In Chinese folklore, it is often portrayed as a companion of the moon goddess Chang'e, constantly pounding the elixir of life for her; but in Japanese and Korean versions it is just pounding mochi.

History

The earliest records suggesting that there is a rabbit on the moon appears in the Warring States period in ancient China. The Chu Ci, a Western Han anthology of Chinese poems from the Warring States period, notes that along with a toad, there is a rabbit on the moon who constantly pounds herbs for the immortals. This notion is supported by later texts, including the Imperial Readings of the Taiping Era encyclopedia of the Song Dynasty. Han Dynasty poets call the rabbit on the moon the Jade Rabbit or the Gold Rabbit (金兔), so in the days of old people also use the words "Jade Rabbit" and "Gold Rabbit" to refer to the moon.

Folklore

The reason why a rabbit is on the moon is described in the Buddhist story "Śaśajâtaka", where a monkey, an otter, a jackal, and a rabbit were friends. Together they resolved to practise charity on the Uposatha day (the day of fast), that was to occur on the following day. In the tradition it was believed that one who stood fast in moral practice and alms-giving on that day would earn a great reward. When an old man begged for food, the monkey was able to gather fruits from the trees, the otter was able to gather dead fish from the river bank, the jackal wrongfully pilfered a lizard and a pot of milk-curd from somebody’s house. The rabbit, wanting to offer something acceptable to the man, was only able to gather grass, and therefore offered its own body instead, and threw itself into a fire that the man built. The rabbit however did not get burned. The old man then revealed himself to be Śakra, and being touched by the rabbit's virtue, drew a picture of the rabbit on the moon to be visible to all. It is said that the smoke-like substance surrounding the lunar image is the smoke that rose when the rabbit cast itself into the fire.
This story can be found in the Konjaku Monogatarishū, a Japanese collection of tales from India, China, and Japan. In this version, however, the rabbit's friends are a fox and a monkey.

Modern references

A popular culture manifestation of this tradition can be found in the character title character of Sailor Moon, whose name is Usagi Tsukino, a Japanese pun on the words "rabbit of the moon." Also, in the dojin game Imperishable Night, a moon rabbit named Reisen Udongein Inaba is the boss of the fifth stage. In Clover Studio's PlayStation 2 game Okami, the rabbit spirit of the Chinese zodiac is depicted making mochi and also grants the player the ability to draw a crescent in the sky to summon the moon.

The moon rabbit was also mentioned in the conversation between Houston and the Apollo 11 crew just before the first moon landing:

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 Chang-o has been living there for 4000 years. It seems she was banished to the moon because she stole the pill for immortality from her husband. You might also look for her companion, a large Chinese rabbit, who is easy to spot since he is only standing on his hind feet in the shade of a cinnamon tree. The name of the rabbit is not recorded.
Collins: Okay, we'll keep a close eye for the bunny girl.

In the manga Pet Shop of Horrors, Count D tells a boy the legend of the Princess and the rabbits on the moon. He also mentions that when the Apollo astronauts landed on the moon, they were all "killed". The boy, however, believes that they are still alive and only hid when the astronauts came.