Columbia Encyclopedia

Search results

500 results found

proper motion

(Encyclopedia)proper motion, in astronomy, apparent movement of a star on the celestial sphere, usually measured as seconds of arc per year; it is due both to the actual relative motions of the sun and the star thr...

harmonic motion

(Encyclopedia)CE5 Harmonic motion is exhibited by a weight vibrating on the end of a spring. In A, the displacement of the object from its equilibrium position and the acceleration of the object are at a maximum...

motion sickness

(Encyclopedia)motion sickness, waves of nausea and vomiting experienced by some people, resulting from the sudden changes in movement of a vehicle. The ailment is also known as seasickness, car sickness, train sick...

retrograde motion

(Encyclopedia)retrograde motion, in astronomy, real or apparent movement of a planet, dwarf planet, moon, asteroid, or comet from east to west relative to the fixed stars. The most common direction of motion in the...

perpetual-motion machine

(Encyclopedia)perpetual-motion machine, device that would be able to operate continuously and supply useful work, in violation of the laws of thermodynamics. A machine that would produce more energy in the form of ...

Motion, Sir Andrew Peter

(Encyclopedia)Motion, Sir Andrew Peter, 1952–, English poet and biographer, poet laureate of England (1999–2009), grad. University College, Oxford (B.A., 1974; M.Litt., 1977). He writes poems that are both lyri...

Hays, Will H.

(Encyclopedia)Hays, Will H., 1879–1954, American politician and motion-picture executive, b. Sullivan, Ind.; his original name was William Harrison Hays. Hays became active in Indiana political affairs, was chair...

Muybridge, Eadweard

(Encyclopedia)Muybridge, Eadweard ĕdˈwərd mīˈbrĭj [key], 1830–1904, English-born photographer and student of animal locomotion. Muybridge changed his name from Edward James Muggeridge. A gifted and obsessed...

Browse by Subject