There were a total of 6 subsystems in the Huygens probe. These included the following.
• Entry Subsystem- This subsystem is made use of only at the time of release of the probe from the orbiter and its subsequent entry into the Titan atmosphere.
• Inner Structure Subsystem- this subsystem consists of two aluminum honeycomb platforms and an aluminum shell.
• Thermal Control subsystem- it is used for temperature control.
• Electric Power Subsystem- this subsystem helps to overcome the loss of any of the five lithium sulphur dioxide (LiSo2) batteries, which supply power to the probe and continue the mission.
• Command and Data Management Subsystem- this subsystem controls and monitors the functioning of all the other subsystems.
• Probe Data Relay Subsystem- this subsystem enables one- way communication between the probe and the orbiter.
Gravity Assist Technology
The Cassini- Huygens spacecraft is huge, which is equipped with a number of instruments to study Saturn. The approximate mass of the spacecraft is 6000 kilograms. However, at the time of launching this spacecraft, there was no launch vehicle that was so strong that could launch the spacecraft into the orbit of Saturn.
The mission designers use the "gravity assist" technique as a solution. In this technique, there is mutual gravitational pull between a moving planet and a spacecraft. The planet pulls on the spacecraft and even the spacecraft's own mass pulls on the planet. This enables exchange of energy, which propels the further movement of the spacecraft.
Cassini-Huygens looped around the Sun twice. The spacecraft flew past Venus once and Earth twice on its journey to Saturn. With the help of these "gravity assist" boosts, Cassini-Huygens had enough orbital momentum to reach the outer solar system. It received a last gravity assist from Jupiter, which provided the spacecraft enough energy to project itself to Saturn.