Word: cm
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Unlike Durante, who tears pianos apart with his bare hands, collegiate wreckers use axes, sledge hammers, iron wedges, crowbars and brooms. Working against the clock, the students must batter a piano into pieces small enough to be passed through a hole in a board 20 cm. (7.87 in.) in diameter. The sport got its start at Britain's Derby College of Technology, where the best time was 14 min. 3 sec. Then, at Caltech, members of the Reduction Study Group claimed the piano-demolition championship by crippling a keyboard in 10 min. 44.4 seconds. But records are made...
Radio astronomers are particularly intrigued by the special waves given off by cold hydrogen floating between the stars. These waves are a little longer than 21 cm. long when they leave the hydrogen cloud where they are generated. If they are slightly shorter than that when they are measured by an earthly radio telescope, this means that the hydrogen cloud must be moving rapidly toward the earth. If the waves are longer, the cloud is moving away. So the 21-cm. waves provide a handy tool for measuring the speed of the hydrogen clouds that form an important part...
...same entity-the nucleon. " The composition of the particles, he pointed out, is nearly alike except for the electrical charge. Each is composed of an outer cloud of moving mesons, a denser inner cloud, and an extremely dense, pointlike core. Both cores are no larger than .00000000000002 cm. Both the clouds and core of the proton are positively charged, while the charge in a neutron is electrically balanced by its inner cloud (negative) and its outer cloud and core (positive). Target for future examination: the heart of the matter, the minute, tightly packed center of the proton...
...farthest end of the space science spectrum is a project to listen for messages sent by intelligent creatures living on planets revolving around other stars than the sun. This project was made plausible by Harvard's Physics Professor Edward Purcell, who was the first to detect the 21-cm. waves from cold hydrogen throughout space. Purcell explains that if intelligent aliens send messages to the earth, they will use a sort of reversed cipher that is deliberately made easy to translate. Their first problem will be to select the proper radio frequency: there is no use picking one at random...
...just laying it out for anyone to do with as they will." It was a spare-time experiment with a borrowed electromagnet and a quarter's worth of paraffin that led to his Nobel-prizewinning "nuclear resonance" system for measuring atomic properties. In his early studies of the 21-cm. radio waves coming from hydrogen clouds in interstellar space, Purcell made do with a hastily devised antenna hung outside his Harvard laboratory. It looked like a horn left over from an ancient phonograph, but it worked...