polar axis: see axis.
polar co-ordinates: see co-ordinates.
polar distance: the distance (as an angle) of the sun from the elevated celestial pole; the complement of the declination.
Polar axis The axis around which a celestial body rotates.
Proper motion The small change in position of nearby stars due to motion across the line of sight (measured in seconds of arc per year).
Polar Axis
The axis of a telescope around which the celestial sphere rotates
Poor Galaxy Cluster ...
polar axis: The axis around which a celestial body rotates.
poor cluster: An irregularly shaped cluster that contains fewer than 1000 galaxies, many spiral, and no giant ellipticals.
Polar Axis
The axis of an equatorially mounted telescope that points towards the Celestial Poles and is therefore parallel to the Earth's axis of rotation.
Polar Motion ...
Polar axis, that axis of an astronomical instrument, as an equatorial, which is parallel to the earths axis. -- Polar bear Zool., a large bear (Ursus, ∨ Thalarctos, maritimus) inhabiting the arctic regions.
polar axis - (n.)
The axis of an equatorial telescope mounting that is parallel to the earth's axis of rotation.
polarization - (n.) ...
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306. Polar Axis
The axis of a telescope around which the celestial sphere rotates.
Of course when the polar axis precesses from one direction to another, then the equatorial plane of the Earth (indicated with the circular grid around the equator) and the associated celestial equator will move too.
Geodetic longitude is the angle between the plane of the reference meridian and the plane through the polar axis and the normal to the spheroid. Geodetic and sometimes astronomical longitude are also called geographic longitude.
equator (NASA Thesaurus / NASA SP-7, 1965) The primary great circle of a sphere or spheroid, such as the earth, perpendicular to the polar axis; or a line resembling or approximating such a circle.
As shown above in Figure 26, the Moon's polar axis is nearly perpendicular to the plane of the ecliptic. As a result, sunlight is always horizontal at the lunar poles, and certain areas, such as crater bottoms, exist in perpetual shadow.
If the course of the Earth around the sun were a precise circle and if the Earth's polar axis stood perpendicular to the plane of its orbit, ...
To track an interplanetary spacecraft, the telescope would point to the spacecraft's known HA and DEC, and then for the rest of the tracking period it would simply rotate in HA about the tilted axis (called its polar axis), as the Earth turns.
The first equatorial mounting, in which one axis, called the polar axis, is parallel to the axis of the earth, is ascribed to the British astronomer William Lassell (1799-1880).
Equatorial Mount - A telescope mount designed with two axes, one of which (the Polar axis) is made parallel to the Earth's axis of rotation.
In this arrangement light from the primary mirror is reflected along the polar axis to focus at a fixed place separate from the moving parts of the telescope, ...
The tube of the telescope is joined to a shaft (the Declination shaft or axis) which rotates in a housing that in turn is joined at right angles to another shaft (The polar axis).
Similarly, where on Earth latitude goes from 90° north to 90° south (or -90°), astronomers prefer the co-latitude, the angle from the polar axis,equal to 0° at the north pole, 90° on the equator, and 180° at the south pole.
As the Earth turns on its polar axis, the satellite travels over all parts of the globe every few revolutions.
Convection of molten iron within the outer liquid core, along with a Coriolis effect caused by the overall planetary rotation, tends to organize these "electric currents" in rolls aligned along the north-south polar axis.
a mount in which the declination axis sits on top of the polar axis, with the telescope on one end of the declination axis and a counterweight on the other
giant molecular cloud ...
The telescope tube is connected to the counter-weighted declination axis, which rotates in a housing that keeps it orthogonal to the polar axis.
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.
coude focus - An optical arrangement in a reflecting telescope whereby light is reflected by two or more secondary mirrors down the polar axis of the telescope to a focus at a place separate from the moving parts of the telescope.
In one, Bootes represents a ploughman who drove the oxen which were tied to the polar axis, in the Ursa Major constellation, with his two dogs, which belong to the constellation Canes Venatici. Bootes' work, in other words, kept the skies turning.
Simulations show that the smaller galaxy passed through the disk of Andromeda along the later's polar axis. This collision stripped more than half the mass from the smaller M32 and created the ring structures in Andromeda.
Already this instrument is producing some exciting science including the discovery that the fast spinning hot star Achernar has an equatorial radius more than 50% larger than its polar axis making it the flattest star known and detailed observations ...
If the weight seems to want to become higher then the scope, you have to turn the scope around on the mount, and then rotate the tube. REMEMBER.. the Polar Axis MUST remain pointing at the North Star.
 See also: Axis, Earth, Sky, Rotation, Time
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