The Cassini trajectory takes the spacecraft past Venus twice and Earth once before beginning its trip to Saturn. This poses a challenge of temperature control, since for the first several years of the mission, the orbiter will be closer to the Sun. The high-gain antenna will be used as a sunshade to shield the rest of the orbiter and probe. Specialized paints are also used on the antenna to reflect and radiate much of the Sun's energy. Later in the mission, as the spacecraft approaches Saturn, the sunlight is approximately one percent that at Earth and extreme cold becomes a concern.
Heat is retained by using a highly efficient insulating blanket that wraps most of the orbiter.
The blanket's outer layer is a three-ply membrane composed of a Kapton core with an aluminized inner surface and a metallic outer surface. The translucent Kapton has a yellow color and, when backed by a shiny aluminum layer, yields an amber appearance. Additional electrical heaters and 1W radioisotope heaters are applied in selected areas. The orbiter requires extensive onboard computing capability, since most of the Cassini mission is performed while the orbiter is not in direct communication with ground controllers on Earth. A typical sequence may operate the spacecraft for four weeks without the need for ground controller intervention.