Geyser gawker: Plans for a closer look at Enceladus

Saturn’s moon Enceladus has been in the spotlight ever since the Cassini spacecraft discovered geysers jetting plumes of water vapor from its south pole (SN: 6/2/07, p. 350). The presence of water, along with organic compounds found on the moon’s surface, are two tantalizing indications that some kind of primitive life may have existed or might still reside on or within this highly reflective moon.

Now planetary scientists are planning to take the closest look yet at the geysers. NASA announced Aug. 1 that it will adjust the orbit of Cassini, originally scheduled to fly past Enceladus next March at a stately distance of about 1,000 kilometers, so that the craft will swoop through plumes 30 to 100 km above the moon’s surface.

To protect sensitive detectors on the robotic craft, engineers may command some of the devices to face away from the venting material, says NASA Associate Administrator for Science Alan Stern. During the March 2008 flyby, Cassini’s radar may also get its first look at Enceladus’ tiger stripes, the linear cracks from which the plumes emanate.