Greetings! The Smithsonian History, Art, and Culture digital collection recently added a number of titles from the special collections housed at the Dibner Library of the History of Science and Technology.
Of particular interest, according to Head of Special Collections, Lilla Verkerdy, are two books containing three laws by Johannes Kepler:
“Astronomia nova and Harmonices mundi are two of the most important astronomical works of the Scientific Revolution. They are being digitized under the aegis of the Smithsonian Institution’s History, Art, and Culture project in the Smithsonian Libraries.
Astronomia nova was published in 1609 and revealed the results of Johannes Kepler’s ten-year long investigation of the motion of Mars. The book provided strong arguments for heliocentrism and contributed valuable insight into the movement of the planets, including the first mention of their elliptical path and the change of their movement to the movement of free floating bodies as opposed to objects on rotating spheres. Bern Dibner, eminent book collector and science historian, describes Astronomia nova among the “Heralds of Science,” his selection of the most significant two hundred works in the development of science, and summarizes the first two Keplerian laws as follows:
- “Planets describe ellipses about the sun in one focus.
- The radius vector drawn from the sun to a planet describes equal areas in equal times.”
The third law of Kepler on planetary motion is included in Harmonices mundi, Kepler’s 1619 book, which discusses harmony and congruence in geometrical forms and physical phenomena. Harmonices mundi is also one of the “Heralds of Science,” and in its description contains Dibner’s rephrasing of the third law: “The square of the period of time of a planet is proportional to the cube of its mean distance from the sun.” And he adds: “With his laws in the harmony of simple mathematical ratios, Kepler, with a thought to Pythagorean Harmony of the Spheres, chose the name for this, his crowning work.”