“Then felt I like some watcher of the skies, when a new planet swims into his ken,” wrote John Keats, describing the discovery of Uranus by William Herschel 50 years before. Here was the first planet to be found since the dawn of civilization, and it would not be the last.
When Herschel saw that pale blue-green dot in 1781, he was looking at a world twice as far out in space as Saturn, the furthest know planet up to that time. No wonder it looked so small, so mysterious, and so unreachable to our sight.
The space program would change all that, and when, in 1986 the Voyager 2 spacecraft flew by Uranus and sent pictures back, what astronomers saw was … not much at all!
Unlike the Voyager photographs showing the stormy atmospheres of Jupiter and Saturn, Uranus seemed featureless, quiet, maybe even dull by comparison – a planet asleep. But no more: Uranus has woken up.
As Uranus swings around the sun in its 84-year orbit and its 90-degree tilted axis – like a marble rolling along in its path – its different hemispheres start to heat up as first one side then the other points at the sun. That is what is happening now, and new photographs taken by the Hubble Space Telescope, show a growing brew of activity in the atmosphere of the seventh planet. And we are looking … fascinated!
Astronomer and researcher Michael Sussman of the UA Lunar and Planetary Sciences Laboratory will discuss some of the new findings in an Arizona Senior Academy lecture entitled “Uranus, The Planet That Woke Up,” next Thursday (Sept. 5) at 3:30 p.m.
Sussman attended Shimer College, earning a B.A. in the natural sciences in 1998. After working in the corporate world for several years, he rediscovered his passion for the planets and went back to school. He earned his Ph.D. in astronomy from New Mexico State University in 2011.
Sussman is currently employed as a post-doctoral research associate at UA’s Lunar & Planetary Laboratory, where he researches the atmospheres of giant planets.
Submitted by Michael Chriss, Academy Village Volunteer