Asteroid Affirmative
Asteroid Impact Ice Age
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Asteroid Impact Ice AgeAsteroids impacts cause debris to block out the sun- leads to ice age- empirically proven AP 87 (Impact of Asteroid is linked to start of Ice Age on Earth”, The New York Times, http://www.nytimes.com/1987/03/16/us/impact-of-asteroid-is-linked-to-start-of-ice-age-on-earth.html, March 16, 1987, CGW) Scientists say an asteroid they believe hit the Earth 2.3 million years ago was 10 times bigger than had been estimated and that its impact would have created an explosion 172 times larger than the biggest hydrogen bomb ever detonated. One of the scientists, Frank Kyte, a geochemist at the University of California, Los Angeles, said that the blast might have helped create the Ice Age. Mr. Kyte and an associate at the university, John Wasson, are scheduled to present their findings Monday in Houston at the annual Lunar and Planetary Science Conference sponsored by the National Aeronautics and Space Administration. Finding Based on Samples Their study was based on analysis of seafloor sediment samples collected in the 1960's by Florida State University researchers aboard the ship Eltanin. Based on their analysis of bits of asteroid debris in the seafloor sediments, the two geochemists reported in 1981 that an enormous asteroid fragment plunged into the southeastern corner of the Pacific, north of Antarctica and west of the tip of South America. After more studies of the sediments, they have revised their estimate of the asteroid's size to at least one-third of a mile wide and perhaps two-thirds of a mile in diameter. Based on that size and an estimated speed at impact of nearly 45,000 miles an hour, the impact would have created an explosion with a force equivalent to that of about 10,000 megatons of TNT, Mr. Kyte said. That is 172 times more powerful than the largest nuclear test blast. The Soviet Union detonated a 58-megaton H-bomb on Oct. 30, 1961, 12,000 feet above the Novaya Zemlya test site, said Chris West, a Department of Energy spokesman in Las Vegas. ''It's the largest object ever to fall to Earth from which we have recovered intact samples, unmelted fragments,'' Mr. Kyte said. ''Prior to this, the largest asteroidal impact from which we ever recovered meteorites was the Meteor Crater in Arizona.'' The geochemists used the amount of asteroid debris in the samples to estimate the asteroid fragment's size. Mr. Kyte said the estimate was based on conservative assumptions about how debris from such an impact would have been distributed on the sea floor. Sunlight May Have Been Blocked The Earth started getting colder about 3.5 million years ago, and sheets of ice covered parts of the continents from about 1.5 half million years ago to about 10,000 years ago, in the Pleistocene Ice Age. There is evidence that the dramatic cooling that caused the glaciation occurred sometime between 2.2 million and 2.5 million years ago, prompting the geochemists to speculate that their asteroid might have spurred the cooling by throwing up debris that blocked sunlight. ''As of now, there is no concrete evidence of a direct relationship between this impact and any environmental change, but this is an important subject for future research,'' said Mr. Wasson. Because the asteroid debris includes volcanic material, the fragment that hit Earth must have been part of an asteroid that was large enough, perhaps 60 miles in diameter, to have undergone volcanic activity at some time, Mr. Kyte said. Asteroid Impact Ice AgeAsteroids Create explosions that help create ice age NYT 87(IMPACT OF ASTEROID IS LINKED TO START OF ICE AGE ON EARTH AP Published: March 16, 1987, http://www.nytimes.com/1987/03/16/us/impact-of-asteroid-is-linked-to-start-of-ice-age-on-earth.html, G.L) Scientists say an asteroid they believe hit the Earth 2.3 million years ago was 10 times bigger than had been estimated and that its impact would have created an explosion 172 times larger than the biggest hydrogen bomb ever detonated. One of the scientists, Frank Kyte, a geochemist at the University of California, Los Angeles, said that the blast might have helped create the Ice Age. Mr. Kyte and an associate at the university, John Wasson, are scheduled to present their findings Monday in Houston at the annual Lunar and Planetary Science Conference sponsored by the National Aeronautics and Space Administration. Finding Based on Samples Their study was based on analysis of seafloor sediment samples collected in the 1960's by Florida State University researchers aboard the ship Eltanin. Based on their analysis of bits of asteroid debris in the seafloor sediments, the two geochemists reported in 1981 that an enormous asteroid fragment plunged into the southeastern corner of the Pacific, north of Antarctica and west of the tip of South America. After more studies of the sediments, they have revised their estimate of the asteroid's size to at least one-third of a mile wide and perhaps two-thirds of a mile in diameter. Based on that size and an estimated speed at impact of nearly 45,000 miles an hour, the impact would have created an explosion with a force equivalent to that of about 10,000 megatons of TNT, Mr. Kyte said. That is 172 times more powerful than the largest nuclear test blast. The Soviet Union detonated a 58-megaton H-bomb on Oct. 30, 1961, 12,000 feet above the Novaya Zemlya test site, said Chris West, a Department of Energy spokesman in Las Vegas. ''It's the largest object ever to fall to Earth from which we have recovered intact samples, unmelted fragments,'' Mr. Kyte said. ''Prior to this, the largest asteroidal impact from which we ever recovered meteorites was the Meteor Crater in Arizona.'' The geochemists used the amount of asteroid debris in the samples to estimate the asteroid fragment's size. Mr. Kyte said the estimate was based on conservative assumptions about how debris from such an impact would have been distributed on the sea floor. Sunlight May Have Been Blocked The Earth started getting colder about 3.5 million years ago, and sheets of ice covered parts of the continents from about 1.5 half million years ago to about 10,000 years ago, in the Pleistocene Ice Age. 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