----- 4 stars ----- The Day the Dinosaurs Died / New Yorker A young paleontologist may have discovered a record of the most significant event in the history of life on Earth. [...] Within two minutes of slamming into Earth, the asteroid, which was at least six miles wide, had gouged a crater about eighteen miles deep and lofted twenty-five trillion metric tons of debris into the atmosphere. Picture the splash of a pebble falling into pond water, but on a planetary scale. When Earth’s crust rebounded, a peak higher than Mt. Everest briefly rose up. The energy released was more than that of a billion Hiroshima bombs, but the blast looked nothing like a nuclear explosion, with its signature mushroom cloud. Instead, the initial blowout formed a “rooster tail,” a gigantic jet of molten material, which exited the atmosphere, some of it fanning out over North America. Much of the material was several times hotter than the surface of the sun, and it set fire to everything within a thousand miles. In addition, an inverted cone of liquefied, superheated rock rose, spread outward as countless red-hot blobs of glass, called tektites, and blanketed the Western Hemisphere. [...] “We have the whole KT event preserved in these sediments,” DePalma said. “With this deposit, we can chart what happened the day the Cretaceous died.” No paleontological site remotely like it had ever been found, and, if DePalma’s hypothesis proves correct, the scientific value of the site will be immense. When Walter Alvarez visited the dig last summer, he was astounded. “It is truly a magnificent site,” he wrote to me, adding that it’s “surely one of the best sites ever found for telling just what happened on the day of the impact.”
Links
Links
Links
----- 4 stars ----- The Day the Dinosaurs Died / New Yorker A young paleontologist may have discovered a record of the most significant event in the history of life on Earth. [...] Within two minutes of slamming into Earth, the asteroid, which was at least six miles wide, had gouged a crater about eighteen miles deep and lofted twenty-five trillion metric tons of debris into the atmosphere. Picture the splash of a pebble falling into pond water, but on a planetary scale. When Earth’s crust rebounded, a peak higher than Mt. Everest briefly rose up. The energy released was more than that of a billion Hiroshima bombs, but the blast looked nothing like a nuclear explosion, with its signature mushroom cloud. Instead, the initial blowout formed a “rooster tail,” a gigantic jet of molten material, which exited the atmosphere, some of it fanning out over North America. Much of the material was several times hotter than the surface of the sun, and it set fire to everything within a thousand miles. In addition, an inverted cone of liquefied, superheated rock rose, spread outward as countless red-hot blobs of glass, called tektites, and blanketed the Western Hemisphere. [...] “We have the whole KT event preserved in these sediments,” DePalma said. “With this deposit, we can chart what happened the day the Cretaceous died.” No paleontological site remotely like it had ever been found, and, if DePalma’s hypothesis proves correct, the scientific value of the site will be immense. When Walter Alvarez visited the dig last summer, he was astounded. “It is truly a magnificent site,” he wrote to me, adding that it’s “surely one of the best sites ever found for telling just what happened on the day of the impact.”