Stardust Reveals Suprising Antonomy of a Comet
"Findings from a historic encounter between NASA's Stardust spacecraft and a comet have revealed a much stranger world than previously believed. The comet's rigid surface, dotted with towering pinnacles, plunging craters, steep cliffs, and dozens of jets spewing violently, has surprised scientists."
http://stardust.jpl.nasa.gov/ for full story(s) and photos.
SteveS