[Scale: 44 x 19 miles. Smallest discernable feature: 118 yards across.] (Ice Rafts Picture) [Scale: Each frame 21 x 26 miles. Smallest discernable feature: 118 yards across.] (Scale Picture)

Ice Rafts Adrift on a Subsurface Sea?

The surface of Europa is not silent; it is a dynamic place where thin sheets of the moon's icy crust, some up to 8 miles across, seem to float like frozen rafts over an unseen "ocean" of liquid water or warmer ice. These fractured blocks are remarkably similar in appearance to Earth's polar ice floes (Sea Ice images below). The false color highlights differences in surface composition. White and blue indicate a blanket of fine ice deposited after the large impact explosion at nearby Pwyll crater; reddish brown hues represent mineral deposits in the ice, released with water vapor from below when the surface was originally disrupted. Left: The Landsat image (bottom frame) of California's San Francisco Bay area is scaled to the same size and resolution as the Europa image (top frame). Extended Caption for Ice Rafts Image Extended Caption for Scale Image