Columbia Encyclopedia

Search results

500 results found

dwarf tree

(Encyclopedia)dwarf tree, in horticultural practice, a tree artificially kept to a smaller size than is normal for average members of the species. This is usually accomplished either by limiting its root space and ...

NASA

(Encyclopedia)NASA: see National Aeronautics and Space Administration. ...

Sagan, Carl Edward

(Encyclopedia)Sagan, Carl Edward sāˈgən [key], 1934–96, American astronomer and popularizer of science, b. New York City. Early in his career he investigated radio emissions from Venus and concluded that the c...

Strategic Air Command

(Encyclopedia)Strategic Air Command (SAC), former command of the U.S. air force (see Air Force, United States Department of the) charged with organizing, training, equipping, administering, and preparing strategic ...

pump

(Encyclopedia)pump, device to lift, transfer, or increase the pressure of a fluid (gas or liquid) or to create a vacuum in an enclosed space by the removal of a gas (see vacuum pumps under vacuum). The centrifugal ...

Lloyd, Seton Howard Frederick

(Encyclopedia)Lloyd, Seton Howard Frederick, 1902–96, English archaeologist. Trained originally as an architect, he gained his first archaeological experience in 1928 as a member of the Egypt Exploration Society'...

endoscope

(Encyclopedia)endoscope, any instrument used to look inside the body. Usually consisting of a fiber-optic tube attached to a viewing device, endoscopes are used to explore and biopsy such areas as the colon and the...

Mather, John Cromwell

(Encyclopedia)Mather, John Cromwell, 1946–, American astrophysicist, b. Roanoke, Va., Ph.D. Univ. of California, Berkeley, 1974. He has been a researcher at NASA's Goddard Space Flight Center in Greenbelt, Md., s...

Browse by Subject