In 1610, Galileo Galilei published a small book describing
astronomical observations that he had made of the skies above
Padua. His homemade telescopes had less magnifying and
resolving power than most beginners’ telescopes sold today, yet
with them he made astonishing discoveries: that the moon has
mountains and other topographical features; that Jupiter is
orbited by satellites, which he called planets; and that the
Milky Way is made up of individual stars. From David Owen,
“The Dark Side: Making War on Light Pollution,” The New Yorker
(20 August 2007): 28