Cassini at Enceladus
The Cassini spacecraft and Saturn's moon Enceladus are getting to be pretty good acquaintances. Cassini's flown by the icy moon twice this year, and it'll pay another call tomorrow. As with the earlier encounters, Cassini will focus its attention on the moon's south pole, where water shoots into space from long cracks in the surface.
Cassini discovered the cracks and the water several years ago. It also found that the cracks are much warmer than the surrounding terrain. This year it's looking at that region in detail. Its observations should help scientists better understand the structure and history of Enceladus. It should also help them learn if the moon has the conditions needed for life.
Thanks to the earlier encounters, they already know that Cassini has most of the conditions for life: heat, water, and the chemical building blocks of life. But scientists aren't sure if the water is in liquid form -- a necessity for life as we know it.
They're also unclear on how long these conditions have existed. They want to know if Enceladus has always had the "hot zone" where the water shoots into space, or if it developed recently. So knowing more about its history will reveal how long it's had conditions that are good for life.
Cassini will fly within a few dozen miles of Enceladus tomorrow, and again just three weeks later. Both encounters will help us all get a lot better acquainted with this intriguing moon.
Script by Damond Benningfield, Copyright 2008
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