Difference between revisions of "Precession of The Equinoxes"
m (1 revision(s)) |
|
(No difference)
| |
Latest revision as of 16:00, 30 April 2007
This definition page has been automatically generated. You can help ExoDictionary by expanding, updating, or correcting it. |
| This autostub has not yet had its initial copyediting proof and may contain significant formatting and even factual errors. You can improve Exodictionary by cleaning up the page markup and verifying that the definition is correct and then removing this tag. |
| This autostub has not yet had its initial categorization proof and may be categorized incorrectly. You can improve Exodictionary by removing inappropriate categories and then removing this tag. |
Precession of The Equinoxes
</dt>
The conical motion of the earth's axis about the
normal to the plane of the ecliptic,
caused by the attractive force of the sun, moon, and other planets on the
equatorial protuberance of the earth.
</dd>
The effect of the sun and moon, called lunisolar precession, is to
produce a westward motion of the equinoxes along the ecliptic. The effect of
other planets, called planetary precession, tends to produce a much smaller
motion eastward along the ecliptic. The resultant motion, called general
precession, is westward along the ecliptic at the rate of about 50.3 seconds
of arc per year. The component of general precession along the celestial
equator, called precession in right ascension, is about 46.1 seconds of arc
per year; and the component along a celestial meridian, called precession in
declination, is about 20.0 seconds of arc per year. [[/a>|/a>
]]
References
This article is based on NASA's Dictionary of Technical Terms for Aerospace Use
