Word: nebula
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Dates: during 1960-1969
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...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...
Most scientists believe that the solar system-sun, planets and all-condensed out of a vast nebula of gas and dust. Graduate Student Craig M. Merrihue of the University of California at Berkeley is even convinced that some of the first objects that condensed are still around and can be identified. They are "chondrules"-round, pea-sized or even smaller globules of stony material. When they happened to be embedded in meteorites, the tiny pebbles were preserved by the cold and vacuum of interplanetary space and lasted for billions of years...
Xenon 129 is a rare xenon isotope that is the descendant of iodine 129, a radioactive form of iodine that was created with the rest of the elements that formed the solar nebula and became extinct not many million years later. Since chondrules contain xenon 129, Merrihue argues that they must have acquired it from the decay of iodine 129. This means that they condensed as droplets during the infancy of the solar system, when everything else in the nebula was dust or gas-and they must be older than the earth...
...which sends out rich chords of radio waves, is not a chief attraction. The astronomers' keenest interest is focused on much more distant space, from which the waves bring news of strange occurrences. The third strongest single source in the sky is a famous astronomical object, the Crab Nebula, the turbulent, gaseous wreck of a star that turned into a supernova and blew itself to shreds on July 11, 1054 A.D.-an event that was duly recorded by Chinese astronomers. After 908 years, the Crab's gases are still churning violently, and as the electrons that they contain...