On March 25, 1655, Saturn‘s largest moon Titan was discovered by astronomer and physicist Christiaan Huygens. Titan is considered as the most Earth-like moon discovered so far and the second largest in the solar system.
Christiaan Huygens was born into an influential family and provided with a decent education all his life, leaning several foreign languages mathematics, logic, and rethoric. His father was friends with Galileo Galilei and René Descartes who early noticed the talents of the young Huygens. He studied mathematics and law at the University of Leiden and later on continued his research at the College of Orange in Breda.
In the field of mathematics and physics, Huygens wrote several publications on probability theory, worked on the law of motion, and became well known for his wave theory of light from 1678. Further achievements were made by the scientists in optics and through designing various clocks like the pendulum clock in 1657.
In the mid-17th century, Christiaan Huygens proposed his theory that the planet Saturn was surrounded by a ‘thin, flat ring, nowhere touching, and inclined to the ecliptic‘ after using his self designed 50 power refracting telescope. With the help of his brother, Huygens built several telescopes, but Titan was discovered with their first one. In 1655, he published his findings and named the moon simply ‘Saturni Luna’. After Giovanni Cassini twenty years later found further moons orbiting Saturn, the moons were named ‘Saturn I – V’. After all Saturn moons were discovered, John Herschel suggested to name it finally Titan.
As current research results suggest, Titan consists of several layers with a hot center. Due to the existence of ammonia it is possible that there are still liquid layers of magma. Special on Titan is also his thick atmosphere known to be rotating much faster than its surface. Despite the temperatures of about -179°C on the surface, the moon is known to experience wind as well as rain, creating a surface very similar to Earth’s. Many scientists believe that microbial extraterrestrial life could be possible on the satellite.
Saturns Moon Titan: A World with Rivers, Lakes, and Possibly Even Life by Dr. Chris McKay (NASA Ames Research Center)
References and Further Reading:
-  Titan at NASA
-  Christiaan Huygens at ESA
-  Christiaan Huygens at Britannica Online
-  James Keeler and the Rings of Saturn, SciHi Blog, September 10, 2017
-  Giovanni Cassini and the Saturn Moon Rhea, SciHi Blog, December 23, 2012
-  The Exploration of Saturn, SciHi Blog, August 25, 2012
-  Mariner 10 and the Swing-By at Planet Venus, SciHi Blog, February 5, 2018
-  Christiaan Huygens at Wikidata
-  Christiaan Huygens Timeline at Wikidata