Biography of Christiaan Huygens, Prolific Scientist

Christiaan Huygens (April 14, 1629-July 8, 1695), a Dutch natural scientist, was one of the great figures of the scientific revolution. While his best-known invention is the pendulum clock, Huygens is remembered for a wide range of inventions and discoveries in the fields of physics, mathematics, astronomy, and horology. In addition to creating the influential timekeeping device, Huygens discovered the shape of Saturn's rings, the moon Titan, the wave theory of light, and the formula for centripetal force. 

• Full Name: Christiaan Huygens
• Also Known As: Christian Huyghens
• Occupation: Dutch astronomer, physicist, mathematician, horologist
• Date of Birth: April 14, 1629
• Place of Birth: The Hague, Dutch Republic
• Date of Death: July 8, 1695 (age 66)
• Place of Death: The Hague, Dutch Republic
• Education: University of Leiden, University of Angers
• Spouse: Never married
• Children: None

Key Accomplishments

• Invented the pendulum clock
• Discovered the moon Titan
• Discovered the shape of Saturn's rings
• Formulated the equations for centripetal force, elastic collisions, and diffraction
• Proposed the wave theory of light
• Invented the Huygenian eyepiece for telescopes

Fun Fact: Huygens tended to publish long after making his discoveries. He wanted to make certain his work was correct before submitting it to his peers.

Did You Know? Huygens believed life might be possible on other planets. In "Cosmotheoros," he wrote that the key to extraterrestrial life was the presence of water on other planets.

The Life of Christiaan Huygens

Christiaan Huygens was born on April 14, 1629, in The Hague, Netherlands, to Constantijn Huygens and Suzanna van Baerle. His father was a wealthy diplomat, poet, and musician. Constantijn educated Christiaan at home until he was 16 years old. Christiaan's liberal education included math, geography, logic, and languages, as well as music, horse riding, fencing, and dancing.

Huygens entered the University of Leiden in 1645 to study law and mathematics. In 1647, he entered Orange College in Breda, where his father served as a curator. Following the completion of his studies in 1649, Huygens embarked on a career as a diplomat with Henry, Duke of Nassau. However, the political climate changed, removing the influence of Huygens' father. In 1654, Huygens returned to The Hague to pursue a scholarly life.

Huygens moved to Paris in 1666, where he became a founding member of the French Academy of Sciences. During his time in Paris, he met German philosopher and mathematician Gottfried Wilhelm Leibniz and published "Horologium Oscillatorium." This work included the derivation of the formula for the oscillation of a pendulum, a theory on the mathematics of curves, and the law of centrifugal force.

Huygens returned to The Hague in 1681, where he later died at the age of 66.

Huygens the Horologist

In 1656, Huygens invented the pendulum clock based on Galileo's earlier research into pendulums. The clock became the world's most accurate timepiece and remained so for the next 275 years.

Nonetheless, there were problems with the invention. Huygens had invented the pendulum clock to be used as a marine chronometer, but the rocking motion of a ship prevented the pendulum from functioning properly. As a result, the device wasn't popular. While Huygens successfully filed a patent for his invention in The Hague, he wasn't granted rights in France or England.

Huygens also invented a balance spring watch, independently of Robert Hooke. Huygens patented a pocket watch in 1675.

Huygens the Natural Philosopher

Huygens made many contributions to the fields of mathematics and physics (called "natural philosophy" at the time). He formulated laws to describe the elastic collision between two bodies, wrote a quadratic equation for what would become Newton's second law of motion, wrote the first treatise about probability theory, and derived the formula for centripetal force.

However, he is best remembered for his work in optics. He may have been the inventor of the magic lantern, an early type of image projector. He experimented with birefringence (double diffraction), which he explained with a wave theory of light. Huygens' wave theory was published in 1690 in "Traité de la lumière." The wave theory was in opposition to Newton's corpuscular theory of light. Huygens' theory was not proven until 1801 when Thomas Young conducted interference experiments.

The Nature of Saturn's Rings and the Discovery of Titan

In 1654, Huygens turned his attention from mathematics to optics. Working alongside his brother, Huygens devised a better method for grinding and polishing lenses. He described the law of refraction, which he used to calculate the focal distance of the lenses and build improved lenses and telescopes.

In 1655, Huygens pointed one of his new telescopes at Saturn. What had once appeared to be vague bulges on the sides of the planet (as seen through inferior telescopes) were revealed to be rings. Huygens could also see that the planet had a large moon, which was named Titan.

Other Contributions

In addition to Huygens' most famous discoveries, he is credited with several other notable contributions:

• Huygens innovated a 31 equal temperament musical scale, which is related to Francisco de Salinas' meantone scale.
• In 1680, Huygens designed an internal combustion engine that used gunpowder as its fuel. He never built it.
• Huygens completed "Cosmotheoros" shortly before his death. It was published posthumously. In addition to discussing the possibility of life on other planets, he proposed that the key criteria for finding extraterrestrial life would be the existence of water. He also proposed a method for estimating distances between stars.

Selected Published Works

• 1651: Cyclometriae
• 1656: De Saturni Luna observatio nova (about the discovery of TItan)
• 1659:Systema saturnium (about the planet Saturn)
• 1659: De vi centrifuga (about centrifugal force, published in 1703)
• 1673: Horologium oscillatorium sive de motu pendularium (design of the pendulum clock)
• 1684: Astroscopia Compendiaria tubi optici molimine liberata (compound telescopes without a tube)
• 1690: Traité de la lumière (treatise on light)
• 1691:Lettre touchant le cycle harmonique (about the 31-tone system)
• 1698: Cosmotheoros (about cosmology and life in the universe)

Sources

Andriesse, C. D. "Huygens: The Man Behind the Principle." Sally Miedema (Translator), 1st Edition, Cambridge University Press, September 26, 2005.

Basnage, Henri of Beauval. "Letter from Mr. Huygens to the Author concerning the Harmonic Cycle." Stichting Huygens-Fokker, October 1691, Rotterdam.

Huygens, Christian. "Christiani Hugenii ... Astroscopia compendiaria, tubi optici molimine liberata." Astronomical instruments, Leers, 1684.

Huygens, Christiaan. "Cristiani Hugenii Zulichemii, Const. f. Systema Saturnium : sive, De causis mirandorum Saturni phaenomenôn, et comite ejus Planeta Novo." Vlacq, Adriaan (printer), Jacob Hollingworth (former owner), Smithsonian Libraries, Hagae-Comitis, 1659.

"Huygens, Christiaan (Also Huyghens, Christian)." Encyclopedia, November 6, 2019.

Huygens, Christiaan. "Treatise On Light." Osmania University. Universallibrary, Macmillan And Company Limited, 1912.

Mahoney, M.S. (translator). "Christian Huygens On Centrifugal Force." De vi centrifuga, in Oeuvres complètes, Vol. XVI, Princeton University, 2019, Princeton, NJ.

"The Cosmotheoros of Christiaan Huygens (1698)." Adriaan Moetjens in The Hague, Utrecht University, 1698.

Yoder, Joella. "A Catalogue of the Manuscripts of Christiaan Huygens including a concordance with his Oeuvres Complètes." History of Science and Medicine Library, BRILL, May 17, 2013.

Yoder, Joella. "Unrolling Time." Cambridge University Press, July 8, 2004.