When Cassini-Huygens spacecraft arrived in 2004, it quickly discovered that Saturn’s neighbourhood was much bigger and denser than expected. There are at least 69 moons we are now aware of, thanks to Cassini snooping around, but there are probably more to be discovered.
For 13 years, Cassini has been orbiting what is arguably the most beautiful planet that isn’t Earth in our solar system. It has photographed Saturn thousands of times from various angles. It has also documented the thickness and weirdness of its multiple rings and catalogued its moons from afar.
Early in the mission, the Huygens lander separated from the Cassini orbiter and lit off for the hydrocarbon wilderness of Titan, Saturn’s largest and most fascinating moon.
In doing so, Huygens became the first spacecraft to land on a moon other than our own. That in itself became an impressive technological feat that got lost in the relentless successes of the overall mission.
While a close-up look at Titan with its frozen lakes and rivers was expected to be one of many highlights of the mission, what absolutely blew scientists away was discovering the water and snow-like plumes jetting up miles from the surface of the moon Enceladus. That was not expected when the mission was put together.
Cassini flew through the snow and ice plumes during its many drives-by of the moon, but it isn’t carrying technology designed to detect and analyse microbial life if it is present. That will have to wait for another mission.
As for Cassini itself, all good things must come to an end.
Yesterday, Cassini spacecraft made an intentional death plunge into Saturn, ending a storied mission that scientists say taught us nearly everything we know about Saturn today and transformed the way we think about life elsewhere in the solar system.
Cassini disintegrated as it dove into Saturn’s atmosphere at a speed of 75,000mph (120,700kph).
“The spacecraft is gone,” said Cassini programme manager Earl Maize of Nasa’s Jet Propulsion Laboratory.
“Thanks, and farewell faithful explorer. But the legacy of Cassini has just begun,” he told a press conference afterwards.
“The effect Cassini has – and will have – on the future of planetary exploration will go on for decades.”
Back on Earth, scientists listened for Cassini’s last gasp and mourned its passing. Cassini has been our most reliable set of eyes and ears in that sector of our mysterious planetary neighbourhood. It has transmitted hundreds of thousands of breathtaking images of worlds that humans may or may not ever see up close.
In doing so, Cassini has made the vastness of our solar system a little more intimate. As a species, we are so much more enriched by the Cassini-Huygens mission. Future missions will do even more, but that doesn’t detract from Cassini’s monumental achievement. Well done, good and faithful spacecraft.
