Cassini at Enceladus
Enceladus is not just one of the moons of Saturn — it’s one of the treasures of the solar system. Water squirts into space from cracks in its icy crust — most likely fed by a lake of salty water below the crust. The combination of water, minerals, and the heat source that keeps the water from freezing gives the lake the basic ingredients for life.
The spacecraft that has painted this amazing portrait of Enceladus will take another close look at the moon tomorrow. Cassini will skim just 300 miles or so above the surface. It’ll use several of its instruments to study the plumes of water and ice, and the “hotspots” from whence they come.
Cassini will also use an instrument it hasn’t yet aimed at Enceladus: its radar.
It has used the radar to study Saturn’s largest moon, Titan. An orange haze tops Titan’s atmosphere, so we can’t see its surface. But the radar peers through the haze, allowing scientists to map the surface. The maps show lakes of liquid methane, river channels, giant dunes, and possible ice volcanoes.
Using Cassini’s radar to study Enceladus will help the scientists compare the two worlds — a pair of solar system treasures.
Saturn is quite low in the east at first light. It looks like a golden star, with the true star Spica to its lower right. Titan is visible through modest telescopes as a tiny “star” quite near Saturn. To see Enceladus, though, you need a bigger telescope — or a spacecraft like Cassini.
Script by Damond Benningfield, Copyright 2011
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