Moons reveal their makeover secret

 作者:宫绍     |      日期:2017-12-25 03:02:21
SANDBLASTING is the key to a sparkling complexion – at least for Saturn’s moons. Astronomers first observed Saturn’s moons in detail in 2005 using the Hubble Space Telescope, during a rare perfect alignment of the sun, Earth and Saturn. They found that some of the moons, such as Tethys, shown below, are dazzlingly white, but no one could explain why they have such reflective surfaces. Now Anne Verbiscer at the University of Virginia, Charlottesville, and her colleagues have an answer. They believe that one of the moons, the icy Enceladus,