The Cassini–Huygens mission is a cooperative endeavor by NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a spacecraft to study the planet Saturn and its system, including its moons and rings. The spacecraft consists of two main elements: the Cassini orbiter, which is designed to perform long-term studies of Saturn, its atmosphere, magnetosphere, and rings; and the Huygens probe, which will detach from the orbiter and descend into Titan’s atmosphere to study its surface and conditions.
The mission is named after two astronomers who made major contributions to our understanding of Saturn: Giovanni Domenico Cassini, who discovered four of Saturn’s moons in 1671 – Iapetus, Rhea, Tethys and Dione – as well as gaps in Saturn’s rings now known as Cassini Division; and Christiaan Huygens, who discovered Titan in 1655.
The overall scientific objective of the mission is to understand how giant planets form and evolve. In particular, the mission aims to:
* Investigate why Jupiter and Saturn are so different despite being formed under similar conditions;
* Study how giant planets influence their moons;
* Determine how various ring systems around giant planets form; * Understand how small bodies like comets interact with giant planets. By studying Saturn – a gas giant with an extensive system of satellites comparable in complexity to that found around Jupiter – scientists will gain important new insights that can be applied more broadly across planetary science.