As reported earlier this week, the Cassini spacecraft is now preparing to make a series of very close passes by the edges of Saturn’s rings, known as Ring-Grazing Orbits. A couple days ago, Cassini conducted a close flyby of Saturn’s largest moon Titan; this is the second-to-last ever flyby of Titan before Cassini enters the Grand Finale phase of its mission, culminating in a deliberate plunge into Saturn’s atmosphere on Sept. 15, 2017. During this flyby, Cassini focused on mapping the surface and surface temperatures and used Titan’s gravity to help place the spacecraft into the Ring-Grazing Orbits.
A beautiful image of Saturn’s moon Enceladus with its active water vapour geysers, taken by the Cassini spacecraft. The left side of the moon is lit by the Sun and the right side is illuminated by light reflected from Saturn, or “Saturnshine.” The geysers, over 100 known, originate from a subsurface global ocean and are known to contain water vapour, ice particles, salts and organics. The water vapour reaches the surface through cracks in the outer icy crust.
The Cassini spacecraft’s discoveries about the tiny moon Enceladus have been some of the most exciting of the entire mission at Saturn. What was once thought to likely be little more than a frozen ice world has turned out to be one of the best places in the Solar System to search for evidence of possible life, with its subsurface salty ocean and huge geysers of water vapor. Now, Cassini is preparing for its last close flyby of this intriguing moon and has also made new findings regarding the potential habitability of the ocean below as well as the nature of the geysers.
The Cassini spacecraft has successfully completed its deepest dive through the water vapour geysers of Enceladus and is now sending back some fantastic images of the event. These and subsequent images, as well as science data still to come, will help scientists better understand the incredible active geology occurring on this tiny, cold moon of Saturn.
Today, Wednesday, Oct. 28, 2015, the Cassini spacecraft will make a historic close flyby (dubbed “E21”) of Saturn’s tiny icy moon Enceladus, not only passing very close to the surface, but also making the deepest dive yet through the water vapour geysers which erupt from the south pole. These plumes are connected to a global ocean of salty water deep below the surface ice, which may be a habitable environment for some form of life.