Sejong Develops Korean Celestial Globe

1443

King Sejong's court astronomers constructed the Honcheonui, an armillary sphere that modeled celestial movements with unprecedented accuracy for East Asian instrument-making. Paired with the rain gauges, water clocks, sundials, and printed star maps his court had already produced, it completed a national scientific infrastructure that made Joseon Korea the most empirically advanced state in all of fifteenth-century Asia, a distinction that has been consistently underappreciated by Western historiography.