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.
The Cassini mission to Saturn has been one of the most successful planetary missions ever, revealing the ringed giant and its moons as never before. Sadly, that mission is scheduled to end Sept. 15, 2017, and in preparation the spacecraft will be making some never-done-before maneuvers as it gets ready to take the final plunge into Saturn’s atmosphere on that date, aka the Grand Finale. Next week, Cassini will perform one of these feats, flying just past the edge of Saturn’s main rings.
This image shows the stars Alpha Centauri A and Alpha Centauri B just above the edge of the cloud tops in Saturn’s atmosphere, as seen by the Cassini spacecraft. The two stars are part of the Alpha Centauri triple star system, which is the closest star system to our Solar System, but is still almost 30,000 times farther away from us than Saturn is.
The Cassini spacecraft has been orbiting Saturn for many years now, studying the massive planet and its moons in unprecedented detail. Now, Cassini might be able to help shed light on another Solar System mystery: the possible existence of a ninth planet in the outer Solar System far past Pluto, or “Planet Nine” as it has been dubbed. There is also a new report, based on old data, that the Huygens lander observed methane ground fog as it descended to the surface of Saturn’s moon Titan in 2005.
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.