Powerful jets of water and ice shoot into space from the south pole of Enceladus, a moon of Saturn, in this 2009 composite image from the Cassini spacecraft. (The image has been rotated so that south is "up.") The water squirts through narrow cracks, called tiger stripes. It may come from a large ocean of mineral-rich liquid water below the moon's surface. Cassini has made several passes by Enceladus, and will swing just 50 miles above its surface on March 27. [NASA/JPL/SSI]
StarDate [1]: Monday, March 26, 2012
The Cassini spacecraft has a busy few days coming up. The probe will scan five of the moons of Saturn, taking a look at everything from clouds to geysers.
Throughout the period, Cassini will take regular looks at the largest moon, Titan. It’s enveloped by a thick, cold atmosphere, with clouds of frozen methane floating through its skies. Cassini will watch the motions of the clouds to plot the big moon’s weather.
The craft will also look for tiny moons orbiting Titan itself, as well as another moon, Rhea. And it’ll make its closest approach yet to the small moon Janus, which shares an orbit with yet another moon. The two of them work together to clear out a gap in Saturn’s rings.
The star of the week, though, is Enceladus. Geysers of water and ice shoot into space from “hot spots” near the moon’s south pole. Cassini has taken several close looks at that region, and at the geysers.
Tomorrow, it’s scheduled to swoop to within 50 miles of the surface of Enceladus. The craft will approach from the nightside, so it’ll see the spray of ice backlit by the Sun. It’ll then pass around to the dayside, providing a 3D view of the geysers, plus one of the best looks yet at the hot spots that give them birth.
Enceladus is too small and faint to see without a telescope. But Saturn is in good view. The bright golden planet rises in mid evening, close to the left of Spica, the brightest star of Virgo. The pair arcs high across the south during the night.
Script by Damond Benningfield, Copyright 2012
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