A satellite streaks in front of a pair of interacting galaxies in this Hubble Space Telescope image. The number of orbiting satellites is increasing by several thousand per year, presenting a big challenge for the scientists who operate telescopes in space and on the ground. The proliferation also could make it more difficult for casual skywatchers to see the Milky Way, faint meteors, and other cosmic sights. [NASA/ESA/STScI]