"Earthly Stars (Unsung Heroes)" (地上の星^?, Chijō no Hoshi) is a song that Japanese musician Miyuki Nakajima composed and recorded for the country's acclaimed television documentary program Project X -Chōsenshatachi-, which aired on NHK during the first half of the 2000s. It was released as a double A-Side single with "Headlight, Taillight" (ヘッドライト・テールライト^?, Heddoraito Tēruraito) in July 2000 and reached the number-one spot after 30 months, becoming one of the longest running singles in history of the Japanese Oricon chart started in 1968.

After a couple of commercially lackluster studio albums were released, Nakajima left Pony Canyon, a record label she had belonged to since her debut. Double A-Side single "Earthly Stars (Unsung Heroes)"/"Headlight, Taillight" is the first release under the record label, Yamaha Music Communications, which was newly founded in 2000.

Both songs were originally written for the TV documentary series Project X: Challengers (プロジェクトX～挑戦者たち～^?, purojekuto X chōsenshatachi) which was aired on NHK. Akira Imai, a producer of the television program decided to ask Nakajima to write theme songs, because he was moved by lyrics of her 1998 smash hit "Another Name for Life". Imai thought that her insight on the song coincided with concept of a documentary that reports unknown activities of obscure people, who built up the modern Japanese society. The program premiered in March 2000, and her theme song which features her distinctive vocals widely became known.

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