Word: polarity
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Dates: during 1980-1989
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...most dramatic manifestation of the solar flare was the two-night, spectacular display of the aurora borealis, or northern lights, that awed Paul Avellar and millions of others. Arriving high-energy electrons, deflected by the earth's magnetic field, spilled into the upper atmosphere near the north and south polar regions, which are unprotected by magnetic-field lines. Acting much as does the electrical current in a neon sign, the electrons banged into oxygen atoms, causing them to emit red and green light...
...platforms called the earth- observing system (EOS). Designed to operate for at least 15 years, the satellites would give scientists their first comprehensive look at just how the world's environment changes over time. Detectors would monitor the shrinking of the tropical rain forests as well as of the polar ice caps (a possible consequence of global warming). One instrument would measure the stress of pollution on the leaves of trees, while another would monitor the health of small ponds. Data from all the detectors would be correlated in an unprecedented effort to understand the interactions of earth...
...anti-drilling activists argue that the area is just too sensitive to stand the strain of oil production, even if a spill never occurs. A few roads and airstrips in this seemingly vast wilderness, they say, could cause permanent harm to the habitats of caribou, musk-oxen, polar bears, golden eagles and wolves. For evidence to back their argument, the preservationists point to Prudhoe Bay. The weight of trucks atop temporary roads has cut into the mat of vegetation that makes up the tundra, allowing sunlight to weaken the top layer of permafrost beneath. The result: ever deepening ruts that...
...Energy and Natural Resources approved legislation to allow drilling in Alaska's Arctic National Wildlife Refuge. Experts believe the field may hold enough oil to supply U.S. needs for about 20 months. But the bill will face fierce opposition from conservationists who argue that drilling could destroy caribou, polar bears and other wildlife. Opposition could be bolstered by last week's Alaskan oil spill...
...this year proceeds as planned, NASA intends to keep up the momentum. In 1990 shuttles are scheduled to launch the ROSAT X-ray telescope, the Gamma Ray Observatory and Ulysses, the first probe to study the sun's polar regions. But some experts worry about relying too heavily on the shuttle. "I certainly hope that these missions will go off as planned," says James Van Allen, the University of Iowa physicist who discovered the Van Allen radiation belts that ring the earth. "But the shuttle is not out of the woods yet. After Challenger, NASA should have made a decision...