can command a robotic observatory while lounging at home.
10. Most professional astronomers now work that way too, operating telescopes remotely with computers and rarely looking through an eyepiece.
11. Long time coming: NASA launched the Hubble Space Telescope in 1990, seven years late and $ 2 billion over budget.
12. Hubble’ s eight-foot light-collecting mirror had to be polished continuously for a year to an accuracy of 10 nanometers, about 1 / 10,000 the width of a human hair.
13. Unfortunately, the contractors polished the mirror precisely wrong, off by a painful 2,200 nanometers.
14. Since the problem was fixed in 1993 by installing corrective lenses, Hubble has become the source of roughly 25 percent of all published astronomy research papers.
15. Telescopes that pick up radio waves, not visible light, got their start in 1932 when engineer Karl Jansky noticed that the static plaguing his equipment varied on a daily schedule. His antenna was picking up celestial radio sources rotating in and out of view.
16. In 1965 engineers Arno Penzias and Robert Wilson were also bugged by microwave static, this time from every part of the sky. After eliminating poop from roosting pigeons as the cause, they realized they’ d discovered the cosmic microwave background, the Big Bang’ s afterglow.
17. See for yourself: Tune an old analog TV to an empty channel. Much of that“ snow” is from the cosmic microwave background.