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...mechanism which causes giant explosions on the face of the sun--solar flares. The most important concept for analyzing the records is the fact that the frequency of a radio outburst corresponds to the height above the sun's surface emit high frequency signals; bases higher in the solar corona radiate at lower frequencies. Thus, a change in the frequency of a solar signal is caused by a change in the height of the emitting region. With this in mind four general types of solar outbursts have been distinguished...

Author: By Peter Cummings, | Title: Harvard Astronomers Study Solar Rays | 10/30/1963 | See Source »

...Noise Storm. A noise storm consists of a series of short individual bursts of radiation, each lasting a minute or less. The source of these bursts is a turbulent area in the corona above an active sunspot. An entire noise storm may last for hours of days. The bursts are generally confined to a narrow range of frequencies, not greater than 30 megacycles, because the emitting region is at a fairly constant height in the corona...

Author: By Peter Cummings, | Title: Harvard Astronomers Study Solar Rays | 10/30/1963 | See Source »

...These bursts also drift from high to low frequencies, but with great rapidity. Each burst lasts roughly one second, and the drift rate corresponds to an outward velocity of 100,000 km/sec. Such radiation may be due either to fast traveling nuclear particles of to shock waves in the corona. Although Type III events have been associated with numerous small flares, they do not appear to have any effect on the earth...

Author: By Peter Cummings, | Title: Harvard Astronomers Study Solar Rays | 10/30/1963 | See Source »

...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...

Author: By Peter Cummings, | Title: Harvard Astronomers Study Solar Rays | 10/30/1963 | See Source »

People who got a good look at the sun's glowing corona during its recent eclipse may have seen faint veils of light trailing off into space. Appearing as harmless as thistledown, they were visible evidence of the sun's far-reaching violence. Stormy weather on the sun sometimes tosses out clouds of deadly particles, mostly protons, that can kill in a few minutes any humans riding in thin-walled spacecraft. So among the scientists who studied the corona were members of a new, specialized profession: solar meteorology. Their job is to learn to forecast solar weather...

Author: /time Magazine | Title: Astronomy: The Space Condition Forecasters | 8/2/1963 | See Source »

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