Word: antenna
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...miles of earth. Instead of fading almost instantly like an ordinary TV picture, the shot lasts for 200 seconds while a scanning device "reads" it slowly, then transmits it promptly by radio. When the new Tiros comes over the horizon, a ground station operator tracks it with a spiral antenna. Down from the satellite comes a picture of the cloud pattern it has just passed over...
...antenna has a dish 85 feet in diameter made of giant metal plate rather that simple wire mesh. The massive structure, aptly described as a "moveable bridge" can be pointed at any spot in the sky by throwing a switch in the laboratory which has been constructed nearby. Unlike the sweep-frequency receivers, this instrument can only do observations at 950-megacycles (L-band) and 5,000 megacycles (C-band). No other comparable antenna in the world (and there are few of them) is operating at C-band and so any work which Harvard does at this frequency will...
...first serious project with the new antenna was begun early this past summer. Dennis N. Downes '65 and Michael P. Hughes, Dr. Maxwell's research associate at the station, observed the passage of the solar corona in front of the Crab Nebula. In late June the Crab Nebula, the gaseous remnants of a star which exploded in 1054, was in the daytime sky near...
...team of workers at the Air Force Cambridge Research Laboratories, using an 85 foot antenna similar to that in Fort Davis, had written a paper announcing that the radio waves from the Cran were sharply distored as they passed through the outer extensions of the sun's atmosphere. The Harvard group repeated the observations and found no distortion...
Later in the summer the new antenna was used to measure the effective temperatures of someof the planets and to map the center of our galaxy at 5,000 megacycles. Operations ended in September, however, because rain water leaked into the equipment at the focus of the giant dish, and caused the receiver to mal-function. Once this equipment is made watertight, work at the station should proceed rapidly. Dr. Maxwells hopes to make extensive studies of individual sources of celestial radiation. With over 100 sources to be examined, the Harvard Radio Astronomy Station will not be idle during...