Chikyu is a piece from gagaku (an ancient Japanese court dance and music).
It is also known as 'Enchiraku' or 'Enikeraku.'
It is a dance performed by a team of four dancers and belongs to the Uho (a style of Japanese court dance and music, or the Komagaku music). It is a Hira-mai Dance (a slow-paced dance) utilizing Koma-sojo (one of Japanese chromatic scale based on A minor). It involves wearing a Kasane-shozoku costume (a costume for Noh) and a mask, and uses a mushi (a piece of cloth) and a betsu-kabuto (Chikyu-specific hat in the form of a phoenix).
It is a Tsugaimai Dance (a performance consisting of two pieces of dance) that involves either 'Manjuraku' or 'Bairo.'
It is believed that Chikyu was performed together with the melody of 'Sakurabito,' a song collected in Saibara (a genre of the Heian-period Japanese court music, which primarily consists of gagaku-styled folk melodies).
There is a story of FUJIWARA no Kinto singing 'Sakurabito' of Saibara while rhythmically tapping a pillar with his fan at the Shishinden Hall (a hall for state ceremonies) around the prime season of the cherry blossoms, when O no Masasuke and others, who were stationed at the guard tower, came out to the garden and danced the Ha (the middle part) of 'Chikyu.'