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microprocessor
(Encyclopedia)microprocessor, integrated circuit containing the arithmetic, logic, and control circuitry required to interpret and execute instructions from a computer program. When combined with other integrated c...aerial and satellite photography
(Encyclopedia)aerial and satellite photography, technology and science of taking still or moving-picture photographs from a camera mounted on a balloon, airplane, satellite, rocket, or spacecraft. In the 19th cent....electron tube
(Encyclopedia)CE5 Triode electron tube electron tube, device consisting of a sealed enclosure in which electrons flow between electrodes separated either by a vacuum (in a vacuum tube) or by an ionized gas at l...Venus, in astronomy
(Encyclopedia)Venus, in astronomy, 2d planet from the sun; it is often called the evening star or morning star and is brighter than any object in the sky except the sun and the moon. Because its orbit lies between ...radio
(Encyclopedia)CE5 A. AM transmitter B. AM receiver radio, transmission or reception of electromagnetic radiation in the radio frequency range. The term is commonly applied also to the equipment used, especially...drone
(Encyclopedia)drone or remotely piloted vehicle, a pilotless craft guided by remote control. Aircraft, ships, and land vehicles can be designed or outfitted as drones. Underwater vessels—both piloted and pilotles...ivory
(Encyclopedia)ivory, type of dentin present only in the tusks of the elephant. Ivory historically has been obtained mainly from Africa, where elephant tusks are larger than they are in Asia, the second major source...Strategic Defense Initiative
(Encyclopedia)Strategic Defense Initiative (SDI), former U.S. government program responsible for research and development of a space-based system to defend the nation from attack by strategic ballistic missiles (se...reflection
(Encyclopedia)CE5 Image formation by curved mirrors and lenses reflection, return of a wave from a surface that it strikes into the medium through which it has traveled. The general principles governing the ref...balloon
(Encyclopedia)balloon, lighter-than-air craft without a propulsion system, lifted by inflation of one or more containers with a gas lighter than air or with heated air. During flight, altitude may be gained by disc...Browse by Subject
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