On the Cover: Among nature’s gifts, dunes exist in a class by themselves. Whatever form they take—from star- or crescent-shaped, to sharp-crested and linear, to sensuous and undulating—they are all fascinating and beautiful. It was late fall in the Aonia Terra region of Mars’ southern hemisphere when the High Resolution Science Experiment (HiRISE) on Mars Reconnaissance Orbiter imaged these dunes. In this colorized view, carbon dioxide frost (bright lavender) is just beginning to accumulate on the dunes’ pole-facing slopes and in the troughs between the meter-scale ripples. NASA/JPL/University of Arizona
8 The Dune Whisperers: Ralph D. Lorenz explores how windblown sand shapes planetary landscapes.
15 China Is On the Moon: Emily Lakdawallareports on China's Chang'e mission to the Moon.
18 Revisiting the Year in Pictures: You—our members—voted on your favorite space image from 2013.
20 Near-Earth Asteroids:Bruce Bettson flying to one and lasering others.
22 A Unifying Cosmos: Casey Dreier discusses the rebirth of Cosmos and its celebration of science.