The Galilean moons, named after their discoverer Galileo Galilei, provide visual proof of the complexity and beauty of the heavens. In this infrared image by the Hubble Space Telescope, two of the four moons are visible (Io, the white circle near the center, and Ganymede, the blue circle in the upper right), along with three of the moons’ shadows (Ganymede’s, Io’s, and Callisto’s, from left to right).
NASA/ESA/E. Karkoschka (University of Arizona)
On December 31, 2009, the International Year of Astronomy (IYA) came to a close. Although IYA-related events still occurred in January 2010, the celebration’s major goal, to inspire the world to look up at the sky, ended with the turn of the calendar.
