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

This summer, you will be able to admire an astronomical spectacle that only occurs every 15 years, and therefore will not happen again until 2040: the face of Saturn will be 'stained' by the shadow cast by its largest moon, Titan, as it orbits it every 16 days. This is because, every 15 years, the Earth and Saturn align perfectly, so much so that the rings disappear from view as happened last March, while in 2032 it will be possible to see the entire disk in a perfect circle around the planet.

Three of these passages have already occurred, but there will be 7 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 from time to time: in October the shadow will be visible for only one minute.

The same phenomenon will also affect other major satellites of Saturn, such as Mimas and Rhea, but their small, bright shadows will be much more difficult to observe.

Titan is in fact the second largest moon in the Solar System after Ganymede, Jupiter's giant satellite: its diameter of over 5,000 kilometers makes it 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 spacecraft. The European Space Agency's Huygens probe landed on Titan in 2005. It was designed to collect atmospheric data during its 2-hour descent, but it continued to send data after landing for over 3 hours, operating at minus 180 degrees.

Saturn (getty)