Yesterday we noted that Mars will be very close to the Earth this Summer. I've been reading old newspaper and magazine articles on the public perception of astronomy and, looking for references on Sputnik and IGY, came across references to the favorable opposition in 1956.
It seems the US when through something of a Martian mania that year. New explanations of the canals (even against serious evidence that they didn't exist) caught the public imagination as did pieces in Collier's and Life. a beautiful book called The Exploration of Mars (I had a copy) and films from Paramount and Disney. It seems that Wernher von Braun had been cultivating the media by partnering with Chesley Bonestell in preparation for what he knew would be a space race. (Chuck Jones was thinking about Martians even earlier...)
Newspapers were following along publishing much of this and Mars was the right thing to capture the public imagination. Cleveland saw over 10,000 visitors a night lined up for a brief look through a 9 inch refractor at the Warner and Swasey Observatory. Griffith Park experienced monumental traffic jams and sky parties with amateur astronomers showing the mars to the public through homemade six inch reflectors were common.
The most interesting tidbit I came across was some work done by Bob Leighton of Caltech. Leighton, in addition to being a crack experimental physicist, was an avid amateur astronomer. He had noticed that planetary images tended to jump in whole rather than distort and made some accurate conjectures about the optical nature of "seeing" conditions through the Earth's atmosphere. He noted that this jumping wasn't terribly fast and built the world's first piece of adaptive optics for a telescope. Since some of you are physicists, here is his description
(he used a beamsplitter to direct a bit of the light from his telescope onto a pair of PMTs, whose output controlled the orientation of a lens in the optical train)
The signals from these tubes are amplified in separate direct current channels and fed into the electromagnet coils that determine the position of the magnifying lens. The system seeks a stable condition wherein a certain amount of light is entering each phototube. If the image moves by a small amount, the amount of light entering each of the photocells changes, and the system responds in such a way as to cancel out this motion.
Leighton stopped down the 60 inch reflector at Mount Wilson to 21 inches and took a 20 second exposure on a slow color film (ISO 40) at 750 power. His adaptive optics worked well enough to give the best color photo of Mars until spacecraft visited the planet.
Leighton was an impressive character. Among other things he invented spin-casting of large telescope mirrors, directed the early Mariner probe efforts at JPL, and built designed very interesting telescopes including the first large infrared telescope. He died about 5 years ago, but was very active in interferometer telescopes.
Very neat guy - he and Feynman used to hang out together.
5:38:27 AM 
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