Celestial Pole
Related Category: Astronomy: General
one of the two points at which the earth's axis of rotation intersects the celestial sphere.
Celestial Poles
The celestial poles are the two points where the projection of the Earth's rotation axis intersects with the celestial sphere.
Celestial pole
The two celestial poles are the imaginary points where the Earth's spin axis intersects the imaginary rotating sphere of stars called the celestial sphere.
celestial pole
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Celestial Pole
This entry contributed by Dana Romero
The celestial poles are the projections of the Earth's north and south poles into the . Because of , these poles wander along a circle with a period of about 26,000 years.
The celestial poles have no physical relevance other than as convenient reference points for terrestial astronomy and navigation.
Its only notable feature is the South Celestial Pole, with is marked (within a degree or so) by the faint star σ Octantis, and is identified above.
IRAS Mosaic of the South Celestial Pole
The infrared sky at the south celestial polar cap is displayed in this image constructed from nine fields of the Infrared Astronomical Satellite (IRAS) Sky Survey Atlas.
Celestial poles Points on the celestial sphere directly above the Earth's poles about which all the stars seem to rotate; known as the north and south celestial poles (NCP and SCP).
celestial pole: the points on the Earth's axis where it meets the celestial sphere. The stars appear to rotate around these poles.
celestial pole
the imaginary projection of Earth's rotational axis onto the celestial sphere
celestial sphere ...
Celestial poles- the imaginary points on the sky where Earth's rotation axis, extended infinitely, would touch the imaginary celestial sphere ...
Celestial pole
the north and south celestial poles are points on the celestial sphere where earths axis of rotation intersects the celestial sphere.
Celestial Poles The two points where Earth's axis of rotation is projected onto the celestial sphere.
Celestial Sphere The projection of space and the objects therein onto an imaginary sphere surrounding the Earth and centred on the observer.
Celestial Poles - The Earth's axis of rotation projected onto the celestial sphere. The celestial poles on the celestial sphere correspond to the North and South rotational poles on the Earth.
celestial pole
The two poles (north and south) of the celestial sphere. The stars rotate around the stationary poles.
Celestial pole -- One of the two points in the sky around which the celestial sphere seems to rotate.
Celestial Poles - these are points on the Celestial Sphere that are directly above the Earth's Poles, so there is a Celestial North Pole and a Celestial South Pole.
Celestial Poles
The two points at which the Earth's axis of rotation, if extended, would intersect the celestial sphere.
Celestial Sphere ...
north celestial pole Point on the celestial sphere directly above the Earth's north pole.
North Celestial Pole - The point above the Earth's north pole where the Earth's polar axis, if extended outward into space, would intersect the celestial sphere.
celestial pole (north or south)
One of the two points on the celestial sphere directly above Earth's poles.
celestial sphere ...
celestial poles - Points about which the celestial sphere appears to rotate, intersections of the celestial sphere with the earth's polar axis.
Celestial Poles
The North and South poles of the celestial sphere.
Celestial Sphere
An imaginary sphere around the Earth on which the stars and planets appear to be positioned.
CELESTIAL POLES
The celestial poles are the projection of the Earth's poles onto the celestial sphere.
CELESTIAL SPHERE
The celestial sphere is an imaginary sphere whose center is the Earth. This sphere is used by to map celestial objects.
south celestial pole Point on the celestial sphere directly above the Earth's south pole.
spacetime A synthesis of the three dimensions of space and of a fourth dimension, time; a hallmark of relativity theory.
North Celestial Pole (NCP)
A direction determined by the projection of the Earth's North Pole onto the celestial sphere. It corresponds to a declination of +90 degrees. The North Star, Polaris, sits roughly at the NCP.
Observable Universe ...
The north celestial pole is the "hub" of the northern sky. All the stars appear to rotate around this hub.
south celestial pole (SCP): projection of the Earth's south pole onto the sky. The SCP altitude = the observer's southern latitude. spacetime the four-dimensional combination of space (three dimensions) and time (the fourth dimension).
The point where Earth's axis intersects the celestial sphere in the Northern Hemisphere is known as the north celestial pole, and it is directly above Earth's North Pole.
From the picture, we can see that those stars near the north celestial pole never set. We call them circumpolar stars. One of the circumpolar star, called Polaris, is special because it is very near the north celestial pole.
North and South Celestial Poles
The north ands south pivots points around which the sky appears to rotate.
Nova ...
Halfway between the celestial poles is the celestial equator, this is a projection of the Earth's equator onto the sky. The stars on the celestial equator will rise due east and set due west.
celestial equator (NASA SP-7, 1965) The primary great circle of the celestial sphere in the equatorial system, everywhere 90° from the celestial poles; the intersection of the extended plane of the equator and the celestial sphere.
At just under a degree from the true North Celestial Pole, HR 286 has the additional distinction of vying for "number 2 pole star," as it is almost exactly at the same angular separation from the Pole as the other candidate, Lambda Ursae Minoris.
celestial pole
celestial sphere
Centaur (minor planet)
Centaurus (constellation)
Centaurus A (NGC 5128)
Centaurus Cluster
Centaurus X-3
Center for Astronomical Adaptive Optics (CAAO)
central meridian
Cepheid variable ...
When at the pole his zenith coincides with the celestial pole, and as the earth revolves on its axis, the heavenly bodies perform their apparent diurnal revolutions in horizontal circles round the zenith.
If you were to go outside on a clear night you would observe the stars spinning around the celestial pole. This point is +90° if you are watching the North Celestial Pole or âˆ'90° if you are observing the Southern Celestial Pole.
In the celestial coordinate system the North and South Celestial Poles are determined by projecting the rotation axis of the Earth to intersect the celestial sphere, which in turn defines a Celestial Equator.
Plancius instructed Keyser to make observations to fill in the constellation-free zone around the south celestial pole.
Tombaugh continued his search another 13 years, and examined the sky from the north celestial pole to 50 deg. south declination, down to magnitude 16-17, sometimes even 18.
Similarly, a Dec of +90 degrees points to the "North Celestial Pole" and -90 degrees points to the "South Celestial Pole." The word Celestial is used to distinguish between, for example, the North Pole in the sky and the North Pole on the Earth.
This is the slow movement of the celestial poles tracing out large circles on the celestial sphere. It is caused by a slow wobble in the Earth's axis due to the gravitational effects of the Sun and Moon on the Earth's equatorial bulge.
(a) Theoretical north-south line on the Earth's surface, or an extension of that line onto the night sky, connecting the observer's zenith with the celestial pole and the horizon. The meridian is used to state directional bearings.
Polaris (alpha UMi) is the current pole star for the Northern Hemisphere; it is 1 degree from the exact Northern celestial pole. In 1780, Sir William Herschel discovered that Polaris was a double star with a faint companion star.
"one second of time"); as one moves away from the celestial equator, one must multiply this factor of 15 by an additional factor (cosine of the declination), because the lines of right ascension get closer and closer as one nears the celestial poles, ...
One axis is pointed at the North or South Celestial Pole, depending on the latitude of the observer, and permits east-to-west travel. This axis is called the Polar or Right Ascension Axis.
The projection onto the sky of the Earth's axis of rotation results in two notable points at opposite directions: the north and south celestial poles. Because of precession, these points trace out circles on the sky.
Another way of finding the invisible equator is to use the fact that it is 90° from the celestial poles. These too are invisible, but can be located because they are the centres of the circles traced out by the stars each day and night.
We get this number by subtracting the sun's declination-23º 27'-from the north celestial pole-90º, which is a point in space the Earth's axis points to.
This is the star that is nearest to the North Celestial Pole. If you stood at the north pole, Polaris would be almost directly overhead. If you can spot Polaris in the sky, you can always tell which way is north.
Meridian is a great circle on the celestial sphere that passes through your zenith and also through both celestial poles. Your meridian line extends all the way around the Earth (and intersects your nadir, on the other side).
Startrails around the South Celestial Pole. (Courtesy of the Anglo-Australian Observatory/Royal Observatory Edinburgh)
(56K GIF)
A young open cluster, NGC 3293. (Courtesy of the Anglo-Australian Observatory/Royal Observatory Edinburgh)
(37K GIF) ...
take place north of the constellation Orion, near the June solstice point at the border of the constellations Taurus and Gemini -- shown on this star chart, where the ecliptic intersects the 6-hour meridian extending from the north celestial pole to ...
Each of the two stars was about 10 degrees from the celestial pole which lay directly between them. When one star was exactly above the other in the sky, astronomers could find a line that pointed due north.
Created between 1750-1754 by French astronomer Nicolas Louis de La Caille from stars found near the south celestial pole. The constellation was originally called Mons Mensae.
This means that it's located near the celestial pole and visible all year round. At least in the northern hemisphere.
Cepheus is king of the mythical land of Ethiopia, not the African country of the same name.
An imaginary arc passing through the celestial poles and through the zenith is called the observer's meridian. The nadir is the direction opposite the zenith: for example, straight down from a spacecraft to the center of the planet.
This small and faint galaxy happens to lay close to North Celestial Pole (see finder chart below) - in 1830s NCP was located within the area covered by the above tiny CCD field! PGC36268 galaxy (16 mag.) is also located nearby.
The most interesting star in the constellation is the faint white giant sigma Octantis, a Delta Scuti type variable star and the nearest star to the South Celestial Pole visible to the naked eye.
 See also: Earth, Sky, Star, Constellation, Degree
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