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

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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
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
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
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
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
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
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
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