Exploring the Enigmatic Worlds of Europa and Enceladus

FAYETTEVILLE, Ark. – The solar system is full of interesting moons – the majority of which orbit Jupiter and Saturn. Two of these moons exhibit evidence of liquid water close to the surfaces: Jupiter’s Europa and Saturn’s Enceladus. Amanda Hendrix, a Cassini scientist on the Ultraviolet Imaging Spectrograph at NASA/JPL, will present a lecture titled “Exploring the Enigmatic Worlds of Europa and Enceladus” at 7 p.m. Thursday, April 16, in the Space Center Theater in the Old Museum Building. The lecture is part of the Spring 2009 Arkansas Public Lectures in Space and Planetary Science and is free and open to the public.

Europa, the focus of NASA’s next outer planets flagship mission, experiences enough tidal stresses from massive Jupiter to maintain a liquid water layer — a subsurface ocean that may harbor life. Europa’s surface exhibits evidence of recent surface activity, including lineaments, triple bands, wedges and icebergs, as well as pits, spots and domes. These surface features suggest communication between the subsurface ocean and the ice shell. The radiation environment in which Europa orbits leads to a sputter-induced thin atmosphere.

Evidence collected by the Cassini spacecraft during multiple flybys suggests that Saturn's moon, Enceladus, could have liquid water reservoirs that erupt in Yellowstone-like geysers. The Cassini spacecraft has collected data, including high-resolution images of the warm south polar region, which reveal icy jets and towering plumes of particles and vapor ejected at high speed.

Hendrix is on the science planning team that plans out the science activities that occur during each icy moon encounter. She has published articles analyzing ultraviolet data of the surfaces of these icy moons from onboard ultraviolet imaging spectrograph instruments.

Please visit http://spacecenter.uark.edu for more information.