By Michael Maccallam
To some, the Cassini satellite may sound vaguely familiar or even have no meaning whatsoever, but to those in the scientific community, the satellite’s impact and contribution to space exploration cannot be overstated. On October 15th 1997, the Cassini satellite was launched, beginning its vast journey to some of the outer reaches of our solar system. For the past 13 years of this mission, the spacecraft has been sending back the most detailed and intricate images of Saturn that man has ever seen, and on the 15th September this year the spacecraft entered its final mission of hurling itself towards the surface of its home planet, as a result of Cassini running out of fuel.
Over the duration of its mission Cassini has overseen some of the most awe-inspiring events of our universe, from the birth of a potential moon to an immense storm that gripped the entire surface of the planet. It has encountered an alien ocean, and many of those working on the team have grown sentimental bonds with the spacecraft, having seen it from its very first take-off to its final launch into Saturn’s toxic atmosphere.
When Cassini originally took off it was accompanied by a European partner, Huygens, which was detached from the Cassini spacecraft in January 2005 to explore Saturn’s moon Titan, sending back invaluable data about its terrain, environment and geology. Together with Cassini, Huygens has helped to discover a watery ocean under the surface of Enceladus, proved that Titan is similar to Earth in terms of its seasonal cycles, and encountered a mysterious and confusing hexagonal jet stream that has raised serious questions about our understanding of physics.
The project has been widely-acclaimed over its long journey, with NASA scientist Curt Niebur describing it as ‘insanely, wildly, beautifully successful’ and Dr Linda Spilker, who has been part of the project since its inception, noting that ‘I’ve worked on Cassini for almost an entire Saturn year. A Saturn year is 30 years, and I’ve worked on Cassini for 29 years.’
One of the major discoveries of the satellite has involved unlocking the secrets of Saturn’s rings, which have captivated mankind for hundreds of years. Cassini has revealed the rings to be a microcosm of its own, with a sort of solar system of its own hidden amongst the rings. In a way, the rings have been described as a time machine, shedding light on the origins of our solar system, including how it was initially formed.
Alongside this, the project has massively fuelled discussions on discovering alien life in our planetary neighbourhood, with winds, rivers and lakes being discovered on Titan, as well as a flyby of Enceladus showing that dozens of Saturn’s planets could be holding deep oceans of water, the widely-accepted key to life.
As fascinating as all of the project’s successes have been, it has inevitably faced many problems, some of which were discovered just as the satellite launched from Earth. One of the most disastrous flaws that was discovered quickly after launch was that Huygens, which was designed to launch onto the surface of Titan, wouldn’t be able to communicate with its mothership Cassini during its descent, meaning that any and all useful data would be completely lost, making this several million dollar investment almost useless. Cassini’s program manager Earl Maize reflected back on this incident and commented that ‘there was a sense of urgency, of importance. This was clearly one of the prime components of the mission and we had to salvage everything we could’, but miraculously a fix was actually found that would solve this catastrophic problem.
Overall, Cassini cost an eye-watering £2.54 billion, travelled 7.9 billion kilometres and lasted 19 years, 11 months and 15 days, and although it has been a turbulent mission requiring a vast amount of patience, no one can argue with the fact that it has been a resounding success. Cassini has unlocked many doors that have been previously locked, and has taught us an invaluable amount about the origins of our universe. Although the mission may be over, there is no doubt that this is just the start of what will be a long and prosperous journey into deep-space travel.