Bad Astronomy

Cassini’s dive through the plume

Last week, the NASA spacecraft Cassini dove through the water and dust plumes erupting from Saturn’s moon Enceladus. It was a success! As Carolyn Porco said,

Yesterday’s grazing flyby over the equatorial regions of Enceladus and through its south polar plume went spectacularly well. Several of the Cassini instruments successfully collected valuable information about the south polar surface and the gaseous/particulate environment above it, and we imaging scientists didn’t do too badly ourselves.

She’s not kidding; the images are incredible. Emily, of course, has already been posting about them; see here and here. My favorite so far is this one:

It shows the north pole of Enceladus, which is heavily cratered. Like Jupiter’s moon Europa, Enceladus is encrusted in water ice, which is why it is so white and why there are large smooth regions; cracks in the surface can let water pour through and refreeze. It’s thought the moon may have an undersurface ocean like Europa does as well.

You can read more about the Cassini dive in their press release.