Protostar (EP)
| "Protostar" | ||||
|---|---|---|---|---|
Normal edition cover | ||||
| Single by JO1 | ||||
| from the album The Star | ||||
| Language | Japanese | |||
| A-side | "Infinity" | |||
| Released | March 4, 2020 | |||
| Recorded | 2019–2020 | |||
| Genre | J-pop | |||
| Length |
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| Label | Lapone Entertainment | |||
| Producer(s) |
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| JO1 singles chronology | ||||
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| Music video | ||||
| "無限大(INFINITY)" on YouTube | ||||
Protostar (stylized in all caps) is an extended play (EP) marketed as the debut single of Japanese boy band JO1, formed through the reality competition show Produce 101 Japan. It also served as the lead single for their first studio album, The Star (2020). The single was released by Lapone Entertainment in three different editions on March 4, 2020, consisting of songs performed on the final episode of the show and three new songs. It features the participation of various South Korean songwriters and production teams such as KZ, Kim Seung-soo, Nthonious, KCKT, Ryan S. Jhun, Andrew Choi, and others.
Upon its release, the single earned the top spot on the Oricon Singles Chart and was certified Platinum by the Recording Industry Association of Japan. According to Oricon, JO1 was the seventh artist to sell over 300,000 copies of a debut single n its first week. The lead track, "Infinity", also topped the Billboard Japan Hot 100.