Planet Mercury Unmasked: Fantastic Photos Of Crazy New Discoveries
There are competing theories about Mercury’s formation. Physical models pictured here invoke one or more giant impacts (left) or the vaporization of surface by a hot solar nebula to remove the planet’s original crust and outer mantle. Image Credit: Left: NASA/JPL/Caltech; Right: Reprinted by permission from Macmillan Publishers Ltd: Nature [473(7348):460–461, © 2011] (NASA) Continue reading »