The NASA Spacecraft Cassini begins the first of it’s last orbits around Saturn today, in the final phase of its mission that has been dubbed the “Grand Finale.” Once the spacecraft’s final orbiting is complete in mid-September it is expected to dive into Saturn’s atmosphere, where it will break up like a meteor after losing contact with Earth, completing its 20-year journey into space. Ultimately destroying it is a preventive measure to avoid contaminating any of Saturn’s orbiting moons with microbes that may still be present aboard the space vehicle.
“As it makes these five dips into Saturn, followed by its final plunge, Cassini will become the first Saturn atmospheric probe,” said Linda Spilker, Cassini project scientist at NASA JPL, in a press release.” It’s long been a goal in planetary exploration to send a dedicated probe into the atmosphere of Saturn, and we’re laying the groundwork for future exploration with this first foray.”
Since it’s launch from Cape Canaveral, Florida in 1997, the NASA mission has provided illuminating insight into Venus, Jupiter and Saturn, where it first arrived in 2004. During it’s first approach before it reached Saturn, the spacecraft observed two storms on the planet merging into a large storm, only the second time such an occurrence was ever recorded.
In May 2004, Cassini discovered two new moons orbiting Saturn that were previously unknown, Methone and Pallene, putting the planet’s known number of moons to 60. Later that year in July, Cassini became the very first spacecraft ever to orbit Saturn, marking a historic milestone for NASA and space exploration.
In January 2005, a probe that shot off of Cassini, the Huygen’s Probe, successfully landed on Saturn’s moon, Titan. The probe still holds the record for the farthest distance from Earth a spacecraft has landed on any planet in the solar system.
Cassini discovered water vapor on Saturn’s icy moon Enceladus in 2005, and scientists found evidence of liquid water in 2006, making it a potential candidate for harboring life beyond Earth. The spacecraft also detected lakes on Saturn’s Moon, Titan, and detected previously unknown rings around Saturn.
The smallest moon of Saturn, Aegaeon, which measures only .4 miles in diameter, was found by Cassini in one of its rings in 2009. And in 2010 around Saturn’s icy moon, Rhea, Cassini detected a thin oxygen atmosphere, the first one of its kind ever confirmed anywhere but Earth.
Cassini’s journey provided scientists with new insight into Saturn and it’s moons, with pictures and data never obtained ever before. Observations of Saturn’s Moon Enceladus found potential indications that it may harbor life, with the presence of a sub-surface ocean beneath its icy outer shell. The geysers of water ice that burst out of Enceladus’ surface make it the most reflective object in our solar system.