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the Axis is perpendicular. And for that reason, if a Body be carried along a line, and at the same time be revolved about a given Axe; the Axe, in all the time of the Body's motion, will continue parallel to it self. Nor is any thing else required to preserve this
Parallelism, than that no other Motion besides these two be impressed upon the Body; for if there be no other third Motion in it, its Axe will continue always parallel to the Right-line, to which it was once parallel.
20:
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During revolution about the Sun, the earth's polar axis exhibits parallelism to
Polaris (also known as the North Star). Although observing parallelism, the orientation of Earth's polar axis exhibits precession—a circular wobbling exhibited by gyroscopes—that results in a 28,000-year-long precessional
242:
To explain the Motion of the
Celestial Bodies about their proper Axes, given in Position, and the Revolutions of them… If a Body be said to be moved about a given Axe, being in other respects not moved, that Axe is suppos'd to be unmov'd, and every point out of it to describe a Circle, to whose Plane
485:
Although these distances seem counterintuitive to residents of the
Northern Hemisphere who experience summer in July and winter in January—the seasons are not nearly as greatly affected by distance as they are by changes in solar illumination caused by the fact that Earth's polar axis is inclined
604:
Under the title of precession instruments, various pieces of apparatus, involving the gyroscope principle, have been in use for a number of years for illustrating the precession of the equinoxes, and the parallelism of the earth's axis as it revolves round the
486:
23.5 degrees from the perpendicular to the ecliptic (the plane of the solar system through or near which most of the planet's orbits travel) and because the Earth exhibits parallelism (currently toward
Polaris, the North Star) as it revolves about the Sun.
523:
cycle. Currently, Earth's polar axis points roughly in the direction of
Polaris (the North Star). As a result of precession, over the next 11,000 years, Earth's axis will precess or wobble so that it assumes an orientation toward the star Vega.
538:
Mathematical
Elements of Natural Philosophy Confirmed by Experiments, Or An Introduction to Sir Isaac Newton's Philosophy ... Translated Into English by J. T. Desaguliers ... The Second Edition, Carefully Review'd and Corrected by the
620:
The
Elements of Astronomy, Physical and Geometrical. By David Gregory ... Done Into English, with Additions and Corrections. To which is Annex'd, Dr. Halley's Synopsis of the Astronomy of Comets .
207:. When the Moon's orbital tilt is aligned with the ecliptic tilt, it is 29 degrees from the ecliptic, while when they are anti-aligned (9 years later), the orbital inclination is only 18 degrees.
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The Axis of the Moon is not perpendicular to the Plane of its Orbit, but a little inclin'd to it: The Axis keeps its
Parallelism in its Motion round the Earth
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is described in modern times as "gyroscopic stiffness" or "rigidity in space". The
Newtonian mechanical explanation is known as the
137:, takes place over the course of 26,000 years. As a result, over the next 11,000 years the Earth's axis will move to point towards
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230:. Prior to the invention of the gyroscope, it had been explained by scientists in various ways. Early modern astronomer
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Astronomy Explained Upon Sir Isaac Newton's Principles ... A New Edition, Corrected. [With Plates.]
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Because of rigidity in space, a gyroscope does not tilt its axis of rotation as the earth rotates.
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Axial parallelism is widely observed in astronomy. For example, the axial parallelism of the
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The Encyclopaedia Britannica: A Dictionary of Arts, Sciences and General Literature
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46:") is the characteristic of a rotating body in which the direction of the axis of
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203:. The Moon's orbital axis precesses a full circle during the 18 year, 10 day
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remain in a fixed direction as that planet rotates around the Sun.
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Axial parallelism of Saturn's rings, in a 17th century work by
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502:. Farmington Hills, MI: Thomson-Gale. p. 105 and 454.
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were used to demonstrate the principle, most notably the
114:(the "North Star") year-round. Together with the Earth's
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Gravesande, W.J.; Desaguliers, J.T.; Newton, I. (1726).
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Minor variation in the direction of the axis, known as
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118:, this is one of the primary reasons for the Earth's
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465:. Farmington Hills, MI: Thomson-Gale. p. 487.
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434:. Jones & Bartlett Learning, LLC. p. 30.
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498:Lerner, K. Lee; Lerner, Brenda Wilmoth (2003).
461:Lerner, K. Lee; Lerner, Brenda Wilmoth (2003).
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339:Petersen, J.; Sack, D.; Gabler, R.E. (2014).
299:Kumar, B.; DeRemer, D.; Marshall, D. (2005).
644:College Physics: Reasoning and Relationships
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164:Axial parallelism can be seen in the Moon's
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199:plane is a key factor in the phenomenon of
187:phase and a lunar eclipse can occur at the
179:approximately every six months, in which a
130:, throughout Earth's orbit around the Sun.
70:'s axis of rotation to remain constant as
16:Characteristic of a spinning body in space
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74:rotates, allowing the devices to measure
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171:. This results in the revolution of the
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66:. It is the same effect that causes a
401:. Springer Netherlands. p. 651.
302:An Illustrated Dictionary of Aviation
155:James Ferguson (Scottish astronomer)
124:stars appear fixed in the night sky
13:
342:Fundamentals of Physical Geography
175:relative to the Earth, causing an
58:, this characteristic is found in
14:
697:
647:. Cengage Learning. p. 299.
623:J. Nicholson ... sold. p. 59
398:Encyclopedia of World Climatology
95:Axial parallelism of the Earth's
428:Rohli, R.V.; Vega, A.J. (2011).
377:. John Cassell. 1856. p. 89
345:. Cengage Learning. p. 18.
253:conservation of angular momentum
595:. R.S. Peale. 1890. p. 351
228:Foucault's gyroscope experiment
681:Technical factors of astrology
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1:
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275:Rotation around a fixed axis
106:The Earth's orbit, with its
99:is a primary reason for the
50:as the object moves through
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145:Other astronomical examples
108:axis tilted at 23.5 degrees
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23:Axial parallelism of Earth
572:. W. Strahan. p. 189
87:Earth's axial parallelism
500:World of earth science
463:World of earth science
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48:rotation remains fixed
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641:Giordano, N. (2012).
566:Ferguson, J. (1673).
395:Oliver, J.E. (2008).
307:McGraw-Hill Education
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617:Gregory, D. (1715).
374:The Popular Educator
234:, a contemporary of
141:instead of Polaris.
126:, such as a "fixed"
32:gyroscopic stiffness
686:Celestial mechanics
60:astronomical bodies
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441:978-1-4496-5591-4
408:978-1-4020-3264-6
352:978-1-285-96971-8
316:978-0-07-139606-6
280:True polar wander
249:gyroscopic effect
210:In addition, the
183:can occur at the
44:rigidity in space
28:Axial parallelism
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270:Polar motion
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431:Climatology
218:Explanation
205:saros cycle
173:lunar nodes
97:tilted axis
675:Categories
660:2022-12-02
627:2022-12-02
599:2022-12-02
576:2022-12-02
546:2022-12-03
539:Translator
447:2022-12-02
414:2022-12-02
381:2022-12-02
358:2022-12-02
322:2022-12-03
286:References
265:Axial tilt
224:gyroscopes
116:axial tilt
238:, wrote:
189:full moon
128:pole star
68:gyroscope
56:astronomy
518:60695883
481:60695883
259:See also
201:eclipses
185:new moon
82:Examples
40:rigidity
120:seasons
112:Polaris
101:seasons
36:inertia
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222:Early
191:phase.
166:tilted
42:, or "
247:This
72:Earth
64:orbit
54:. In
52:space
649:ISBN
605:sun.
514:OCLC
504:ISBN
477:OCLC
467:ISBN
436:ISBN
403:ISBN
347:ISBN
311:ISBN
139:Vega
62:in
38:or
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
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