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in astronomy, the point in the sky directly overhead; more precisely, it is the point at which the celestial spherecelestial sphere,
imaginary sphere of infinite radius with the earth at its center. It is used for describing the positions and motions of stars and other objects. For these purposes, any astronomical object can be thought of as being located at the point where the line of sight
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 is intersected by an upward extension of a plumb line from the observer's location. Its position in the sky thus depends on the direction of the earth's gravitational field at the observer's location. The zenith is a reference point in the altazimuth coordinate systemaltazimuth coordinate system
or horizon coordinate system,
astronomical coordinate system in which the position of a body on the celestial sphere is described relative to an observer's celestial horizon and zenith.
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; its altitude above the celestial horizon is 90°. The angular distance from the zenith to a celestial body is called the zenith distance. The nadir, directly opposite the zenith, has a zenith distance of 180°; the celestial horizon has a zenith distance of 90°.


(religion, spiritualism, and occult)

The zenith is the point in the heavens directly overhead at any given location on Earth. It should be carefully distinguished from the midheaven (with which it is often confused).

What does it mean when you dream about a zenith?

May indicate aspiration and culmination of achievement in the world.


That point of the celestial sphere vertically overhead.


The point on a celestial sphere directly overhead the observer. It is called the observer's zenith. An astronomical zenith is where an imaginary plumb line through the observer and the center of the earth intersects the celestial sphere. A geographical zenith is where a line perpendicular to smooth earth intersects the celestial sphere. These terms, however, are not synonymous. The point 180° from the zenith is called the nadir.


Astronomy the point on the celestial sphere vertically above an observer
References in periodicals archive ?
Methods based on stars observation with use of zenithal cameras are more and more often used to determine astronomic coordinates.
However, for a very low-redundant observable such as E-A zenithal angle, least-squares solution is very far from the correct value and therefore Huber and [L.
Between approximately 19:00 and 20:00 Universal time on [August 11th, they found] a zenithal hourly rate as high as 8,000
The speaker explained that although the quoted zenithal hourly rates (ZHRs) for the Taurid shower--around 10--were relatively low, it rewarded patient observers with a higher proportion of bright slow-moving fireballs than other showers.
Main goal of the described project is developing the method of automatic determination of the astronomical site coordinates [PHI], [LAMBDA] based on zenithal star observations.
Finally, the glass folds inwards on top so that this sheer and rather cinematic foyer is also washed in zenithal light.
The Taurids are sparse at all times, with zenithal hourly rates reaching only about 5 meteors visible per hour even under ideal conditions.
ZHR: zenithal hourly rate; is the expected maximum rate under observing conditions when stars of 6.
Overhead, and well placed for observing, objects in the constellations of Lyra and Cygnus alone will keep you occupied whether you have a small or large telescope, though users of large Dobsonians may find the zenithal hole (also known as 'Dobson's Hole') makes observing this area difficult.
The latter backs a serpentine desk of silver marble leading inwards where the intersection of Siza's axial systems is revealed in a triangular ceiling void with indirect zenithal illumination and rectangular upper openings.
The International Meteor Organization (IMO) lists its peak zenithal hourly rate as just 10.
Leonid radiant altitude at time of observation EZHR = Sky- and radiant altitude-corrected Leonid Zenithal Hourly Rate Table 3.