On Ganymede, water goes from a solid straight to a gas, skipping the liquid phase. In 1998, Hubble’s Space Telescope Imaging Spectrograph took the first ultraviolet images of Ganymede.

NASA's Hubble Space Telescope observations of Jupiter's icy moon Europa have revealed the presence of persistent water vapor—but, mysteriously, only in one hemisphere.

Hubble Space Telescope sees geysers on Jupiter’s moon Europa December 12, 2013 More than 11 years ago This is an artist’s illustration of Europa (foreground), Jupiter (right) and Io (middle).

The Moon, Earth’s nearest celestial neighbor, has fascinated humanity for ages with its ever-changing phases. Each month, the Moon transitions through a series of distinct visual stages ...

Meanwhile the moon is only about 380,000 km from us—and from Hubble. At that distance, Hubble’s resolution surprisingly limits it to resolving objects no smaller than about 90 meters across.