> [...] However, the actual solar year has been known to be around 365.2422 days since the 17th century. Although the difference appears to be too small, it lea

> [...] However, the actual solar year has been known to be around 365.2422 days since the 17th century. Although the difference appears to be too small, it leads to an error of adding 1 extra day every 128 years. To reduce this error, the Gregorian calendar was introduced in October 1582 by Pope Gregory XIII [...] Huh? The error has been known since the 17th century, and its fix came in 1582?