Titan's Shadow on Saturn Puts on a Spectacle, Once-in-15-Year Event

This summer, it will be possible to admire an astronomical spectacle that occurs only every 15 years , and therefore will not happen again until 2040 : the shadow of Saturn's largest moon , Titan, is projected onto its disk as it orbits it every 16 days. This happens because, every 15 years, the Earth and Saturn align perfectly , so much so that the rings disappear from view as happened in March 2025, while in 2032 it will be possible to see the entire disk in a perfect circle around the planet . Three of these transits have already occurred, but there will be seven more opportunities to observe them: July 2 and 18, August 3 and 19 , September 4 and 20 , and finally October 6. The duration of the transits , however, will decrease each time until in October the shadow will be visible for only one minute . The same phenomenon will also affect other moons of Saturn, such as Mimas and Rhea , but their small and bright shadows will be much more difficult to observe . Titan is in fact the second largest moon in the Solar System after Ganymede, the giant satellite of Jupiter: its diameter of over 5,000 kilometers makes it even slightly larger than Mercury and 50% larger than our Moon. Titan is also the only moon in the Solar System, other than Earth's, to have been visited by a man-made space probe. The European Space Agency's Huygens probe landed on Titan in 2005. It was designed to obtain data on the atmosphere during its descent, which lasted more than 2 hours, but continued to send data even after landing for over 3 hours, operating at a temperature of minus 180 degrees.