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The Gas Centrifuge

This machine separates the isotopes of uranium by spinning a gaseous uranium compound. It is expected to play a large role in the Carter Administration's effort to limit the proliferation of nuclear weapons

By Donald R. Olander

Stellar Winds

Stars of various sizes and types are observed to eject matter into space in a slow, steady stream. A number of mechanisms may be responsible for this surprisingly common phenomenon

By Ray J. Weymann

The Hominids of East Turkana

This region on the shore of Lake Turkana in northeastern Kenya is a treasure trove of fossils of early members of the genus Homo and their close relatives dating back 1.5 million years and more

By Alan Walker and Richard E. F. Leakey

The Tomato

The esculent Lycopersicon esculentum, long thought to be poisonous, has become a major U.S. food crop and source of vitamins and minerals, thanks largely to genetic modification and new production technology

By Charles M. Rick

Negative Absolute Temperatures

No substance can be cooled below absolute zero, but some physical systems can have a negative temperature on an absolute scale. Such temperatures are not colder than zero but are hotter than infinity

By Warren G. Proctor

The Thermostat of Vertebrate Animals

The hypothalamus, a structure at the base of the brain, monitors body temperature in a wide variety of animals and maintains it at an optimal level by controlling thermoregulatory mechanisms

By H. Craig Heller, Larry I. Crawshaw and Harold T. Hammel

The Tektite Problem

Did these peculiar bits of glass originate on the earth or on the moon, in volcanic activity or in meteorite impact? The evidence is conflicting and the most reasonable answer is a surprising one

By John A. O'Keefe

Departments

  • 50 and 100 Years Ago, August 1978

  • Science and the Citizen, August 1978

  • Organisms that Capture Currents

  • Letters

    Letters to the Editors, August 1978

  • Recommended

    Books, August 1978

  • Mathematical Recreation

    Mathematical Games, August 1978

  • Amateur Scientist

    The Amateur Scientist, August 1978

  • Departments

    The Authors, August 1978

  • Bibliography, August 1978

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August 1978

See the World from a Different Perspective

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