Launching an unmanned mission to Europa which is one of Jupiter’s moons may be more difficult than previously thought.. The presence of icy stalagmites (without the cave) are what appears to be the challenge. “..Researchers also predict that penitentes, perhaps up to five meters long, could crowd Europa’s surface in a wide band centered on the equator.”
http://news.discovery.com/space/is-europa-too-prickly-to-land-on-131028.htm
nickwinlund 