Word: earths
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Dates: during 1970-1979
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...thought we were in the West then because it was a modern machine-unlike anything we have in the East." When the gas gave out at 15 ft., the balloon fell to earth in a blackberry thicket. The entire flight had taken 30 minutes...
...quasars were about 10 billion light-years from earth (meaning that the light detected at Kitt Peak had left the objects 10 billion years ago), and both were receding from the earth at two-thirds the speed of light. What was most unusual was that they were only some 150,000 light-years apart-a stone's throw by cosmic standards-and had virtually identical light spectrums, which meant that their physical characteristics, as well as their velocities, were the same...
...they suggested that what they might be seeing was two images of the same quasar. How was this possible? More than half a century ago, scientists realized a bizarre consequence of Einstein's general relativity theory: if a very massive object were located almost directly between the earth and a distant star, its tremendous gravity would act as a "gravitational lens" that could bend the starlight into two different paths. To produce the effect observed at Kitt Peak, the astronomers calculated, a huge galaxy or a black hole at least 10 trillion times as massive as the sun would...
Since 1972, geologists have studied Landsat satellite images of the earth's landscape to choose areas to explore for oil, gas, copper and other minerals. Now a scientist with the U.S. Geological Survey has studied such pictures and found that concentrations of sagebrush may indicate deposits of uranium...
Geologist Gary Raines reached that conclusion in 1977 when he studied images of a 13,000-sq.-km (5,000-sq.-mi.) section of the Powder River Basin in northeastern Wyoming and southeastern Montana, taken from 920 km (570 miles) above the earth. He noted that clusters of medium density sagebrush on the photographic maps fell in the same area as known uranium deposits. Further study showed that this type of vegetation pattern coincided with the kind of sandy shale rock formations that often accompany uranium deposits...