One Human Minute by Stanislaw Lem

Author:Stanislaw Lem
Language: eng
Format: mobi, epub, pdf
Tags: Science Fiction
Published: 2011-11-08T22:49:28+00:00

IV

Sixty-five million years ago, on the so-called C-T geological boundary (between the Cretaceous and the Tertiary), a meteorite fell on our planet. It had a diameter of about ten kilometers and contained a considerable amount of iron and iridium. Its mass is estimated to have been over three and a half trillion (3,600,000,000,000) tons. It is unclear whether it was one mass, hence an asteroid from the region between Earth and Mars, or a group of bodies forming the head of a comet. In the geological stratum of this period, iridium and rare earth metals have been discovered in amounts and concentrations not normally found in the Earth's crust. The absence of an impact crater made it difficult to prove the planetary scale of this cataclysm, since craters that appeared later (caused by meteorites a thousand times smaller) left marks on the Earth's surface that are clearly visible today. Most likely, this asteroid or comet did not strike any of the continents but landed in the open ocean – or else the collision took place near a junction of continental plates, and the subsequent shifting obliterated the crater.

A meteor of such size and mass can easily pass through the protective layer of the atmosphere. The energy of the impact, comparable in magnitude to the energy of all the world's nuclear stockpiles (if not larger), turned that body – or group of bodies – into thousands of billions of tons of dust, which the air currents spread over the entire surface of the Earth, creating a cloud so thick and long-lasting that for at least four months photosynthesis ceased in plants on all continents. Darkness reigned; the land surface, no longer heated by the sun's rays, grew much colder than did the ocean, which cooled more slowly. Nevertheless, the marine algae, one of the main sources of atmospheric oxygen, also lost their ability to carry on photosynthesis during that time. As a result, an enormous number of plant and animal species became extinct. The most spectacular extinction was that of the giant reptiles commonly called dinosaurs – although at least several hundred other reptile species died out then, too. The catastrophe occurred at a time when the Earth's climate was gradually cooling, and the large, hairless Mesozoic reptiles found themselves in great difficulty. Even before the cataclysm, their viability had been on the wane for about a million years, as the fossil record reveals. The calcium shells of the dinosaur eggs grew thinner as the millennia passed – testimony to the increasing hardships in feeding and to the worsening climate of the large landmasses.

Computer simulations of such an event, done back in the 1980s, verified its lethal effect on the biosphere. Strangely enough, the phenomenon to which we owe our emergence as a rational species was not introduced into any school curriculum, even though there was not the slightest doubt about the connection between the Cretaceous-Tertiary saurocide and anthropogenesis.

Paleontological research toward the end of the twentieth century proved that the dinosaurs

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