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Third-Generation Nuclear Weapons

Unlike deployed nuclear weapons, which unleash their explosive energy indiscriminately, future nuclear weapons may selectively produce certain types of energy and concentrate them on targets...

By Theodore B. Taylor

How Photoreceptor Cells Respond to Light

New information about how light energy is changed into neural signals shows how an individual photoreceptor cell of the eye registers the absorption of a single photon, or quantum of light...

By Julie L. Schnapf and Denis A. Baylor

The Moons of Uranus

Voyager 2 photographed the five major moons at close range. All have icy surfaces, but they are darker and rockier than Saturn's moons. Early in their history three were geologically vigorous...

By Torrence V. Johnson, Robert Hamilton Brown and Laurence A. Soderblom

Antiviral Therapy

How can one kill a virus and not the host cell in which it is physically and functionally incorporated? New antiviral drugs exploit the subtle molecular contrasts between virus and host...

By Martin S. Hirsch and Joan C. Kaplan

Photovoltaic Power

The technology and economics of converting energy from the sun directly into electricity have improved rapidly. Within 15 years megawatt power plants based on solar cells could be in service...

By Yoshihiro Hamakawa

The Emergence of Animals

Some 570 million years ago animals diversified at an unprecedented rate. New body plans and ways of living emerged in concert with a new kind of community, one characterized by complex food chains...

By Mark A. S. McMenamin

Acoustics of Ancient Chinese Bells

Bronze bell chimes were important orchestral instruments until they vanished from history 2,000 years ago. A chime recovered by archaeologists has revealed their sophisticated acoustical design...

By Sinyan Shen

The First Technology

A young archaeologist re-creates a prehistoric flaked-stone technology in order to understand how our ancestors made and used early stone tools more than two million years ago

By Nicholas Toth


  • 50 And 100 Years Ago: April 1987

  • Science And The Citizen

  • Letters

    Letters to the Editors, April 1987

  • Recommended

    Books, April 1987

  • Amateur Scientist

    The Amateur Scientist, April 1987

  • Departments

    The Authors, April 1987

  • Computer Recreations, April 1987

  • Bibliography, April 1987

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