The Cassini spacecraft scans Titan, the largest moon of Saturn, in this artist's concept. Cassini arrived at the Saturn system on June 11, 2004, when it passed by one of the planet's outer moons, Phoebe. Titan has been a frequent target for the craft, which has used radar and other instruments to peer through the haze at the top of Titan's atmosphere and reveal its surface. [NASA/JPL]
The Saturn-orbiting Cassini spacecraft passed an important milestone back in March: It made its 100th close pass by Titan, the planet’s largest moon. During these encounters, it’s given us our first look beneath the orange haze that veils Titan’s surface. Its instruments have revealed riverbeds, lakes of liquid hydrocarbons, and volcanoes that belch ice.
Cassini entered the Saturn system 10 years ago tomorrow, when it flew past Phoebe, the largest of the planet’s outer moons. It saw a world battered by billions of years of impacts — collisions that may have chipped off fragments that became moons themselves.
In the decade since, Cassini has painted a remarkable picture of the entire Saturn system.
It dropped a probe into Titan’s atmosphere. It’s heard the crackle of lightning from giant thunderstorms on Saturn itself, and mapped hexagonal walls of clouds around its poles. It discovered geysers of water and ice shooting from the south pole of the moon Enceladus. And it’s discovered several small moons inside the planet’s broad rings.
Cassini’s voyage of discovery isn’t over yet. Its mission has been extended through 2017, allowing it to make many more close passes by Titan and other wonders of the Saturn system.
And that system is in great view tonight. Saturn is close to the upper right of the Moon as night falls, shining like a bright golden star.
Script by Damond Benningfield, Copyright 2014
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