Astronomy:
* "De Triangulis Omnimodis" (On Triangles of All Kinds): This groundbreaking work on trigonometry was one of the first systematic treatises on the subject. It introduced trigonometric tables and methods for solving triangles, revolutionizing the field.
* "Ephemerides Astronomicae" (Astronomical Ephemerides): These tables provided precise calculations of planetary positions for the years 1475-1506. They were widely used by astronomers and astrologers for years to come.
* "Kalendarium" (Calendar): This calendar was a major improvement on the Julian calendar, more accurately accounting for the Earth's movement. It was widely distributed and used throughout Europe.
* "De Reformatione Calendarii" (On the Reform of the Calendar): This unfinished work addressed the need for calendar reform, outlining the flaws of the Julian calendar and proposing a more accurate system.
Other Works:
* "De Lateribus et Angulis Triangulorum" (On the Sides and Angles of Triangles): This work explored the relationship between the sides and angles of triangles, further contributing to the development of trigonometry.
* "De Quadratura Circuli" (On the Quadrature of the Circle): Regiomontanus investigated the ancient problem of squaring the circle, attempting to find a perfect square equal in area to a given circle.
* "De Cometa Anni 1472" (On the Comet of 1472): This work documented and analyzed the appearance of a comet, contributing to the scientific understanding of these celestial objects.
Regiomontanus's work contributed significantly to the development of astronomy and mathematics, making him a major figure in the Scientific Revolution. He was also a skilled craftsman and builder, constructing instruments like an armillary sphere and a quadrant that furthered astronomical observation and measurement.