from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The act or an instance of nodding the head.
- n. A wobble in a spinning gyroscope or other rotating body.
- n. Astronomy A small periodic motion of the celestial pole of the earth with respect to the pole of the ecliptic.
- n. Botany A slight curving or circular movement in a stem, as of a twining plant, caused by irregular growth rates of different parts.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. a bobbing motion that accompanies the precession of a spinning rigid body
- n. a nodding motion (of the head etc.)
- n. any of several irregularities in the precession of the equinoxes caused by varying torque applied to the Earth by the Sun and the Moon
- n. the circular motion of the tip of a growing shoot
from the GNU version of the Collaborative International Dictionary of English
- n. The act of nodding.
- n. A very small libratory motion of the earth's axis, by which its inclination to the plane of the ecliptic is constantly varying by a small amount.
- n. The motion of a flower in following the apparent movement of the sun, from the east in the morning to the west in the evening.
- n. Circumnutation.
from The Century Dictionary and Cyclopedia
- n. A nodding.
- n. In pathology, a constant nodding or involuntary shaking of the head.
- n. In astronomy, a small subordinate gyratory movement of the earth's axis, in virtue of which, if it subsisted alone, the pole would describe among the stars, in a period of about nineteen years, a minute ellipse, having its longer axis directed toward the pole of the ecliptic, and the shorter, of course, at right angles to it.
- n. In botany, same as circumnutation.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. uncontrolled nodding
If, however, the spheres were somewhat flattened at the poles, and the axes inclined to each other, then the pull of one mass on the other would cause the polar axes to keep up a constant movement which is called nutation, or nodding.
This phenomenon, known as "nutation," was discovered by the beautiful telescopic researches of Bradley, in 1747.
In addition to this steady decrease, there are also much smaller short term (18.6 years) variations, that is also affected by Sun's gravitation in its depleting angle relative to Earth's, known as nutation.
Note that the observed nutation a lunar effect is much larger than the polar motion from the earthquake, so a question he would have to answer is why there is no apparent cycle in temperature from the former.
Amusingly the effect isn't the impressive-sounding nutation at all as a matter of definition, so no amount of calculation saves him from this boo-boo, but rather just plain polar motion.
And now, friends and countrymen, if the wise and learned philosophers of the elder world, the first observers of nutation and aberration, the discoverers of maddening ether and invisible planets, the inventors of Congreve rockets and Shrapnel shells, should find their hearts disposed to enquire what has America done for the benefit of mankind?
The phenomenon, however, subsequently provided important evidence for Newton's theory of gravity when d'Alembert in 1749 carried out a successful derivation based on rigid body motion and a correct value of the Moon's force derived from the then recently discovered phenomenon of the nutation of the Earth.
“I believe that if we introduce a more tightly focused nutation cycle in our deflector shields, and channel power to the shield generators directly from the warp engines, we can produce sufficient energy for the shields to protect against contamination of the dilithium crystals.”
Each shot is actually millions of separate pulses, each at a slightly different nutation.
Synchronize shield emitter nutation to the warp field coil output frequency.
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