celestial equator

the great circle lying on the celestial sphere the plane of which is perpendicular to the line joining the north and south celestial poles

Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

celestial equator

The great circle in which the extension of the Earth's equatorial plane cuts the celestial sphere. The plane of the celestial (and hence terrestrial) equator is perpendicular to the celestial axis and is the reference plane for the equatorial coordinates right ascension and declination. The orientation of the celestial equator is slowly changing as a result of the precession of the Earth's axis.

Collins Dictionary of Astronomy © Market House Books Ltd, 2006

Celestial Equator

(religion, spiritualism, and occult)

The celestial equator, also termed the equinoctial, is the terrestrial equator imaginarily projected outward from Earth and onto the background of the stars (i.e., against the backdrop of the celestial sphere). Because of the tilt of the Earth on its axis, the celestial equator intersects the ecliptic at an angle of 23½°. Similarly, the celestial poles are the north and south poles projected outward against the backdrop of the celestial sphere.

celestial equator

[sə′les·chəl i′kwād·ər]

(astronomy)

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. Also known as equinoctial.

celestial equator

The great circle of the celestial sphere, in which all points are 90° from the poles. It is the plane of the earth's equator projected onto the celestial sphere. Also called equinoctial.

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References in periodicals archive

Orion: One of the most recognisable constellations, Orion - "The Hunter" - can be seen throughout the world, and is one of the most prominent, located on the celestial equator. Lepus: A constellation lying south of the celestial equator and its more famous neighbour Orion, its name is Latin for "hare".

Stargazing Chart; How to use this 360[bar] view The map shows how the skies above South Wales will look at 10pm tonight. Just face south and hold the map up. You should see the stars in these positions

This fact gave a hint for a hypothesis that the histogram shape may depend not only on the proximity to the equinox moment, but also on the direction the Sun is moving to the celestial equator: from the northern or from the southern hemisphere.

Histograms constructed from the data of [sup.239]Pu alpha-activity manifest a tendency for change in the similar way as at the moments when the Sun, the Moon, Venus, Mars and Mercury intersect the celestial equator

Since the spin axis of the Earth is inclined at 23.44[degrees] to the vertical of its orbital plane, the inclination of the ecliptic (path of Sun) is 23.44[degrees] to the celestial equator (circle through the stars directly over the equator of the Earth).

Solar motion from Australia

The fall equinox begins autumn in the northern hemisphere-the moment when the sun appears to cross the celestial equator and day and night are of approximately equal length.

Diversity calendar

Held between the historic axis of the Park and the N-S meridian line in plan, and clipped by the intersection between the axis of the North Star and the celestial equator in elevation, the edges of the cone could not be anywhere else.

Heavens above! Allies and Morrison make shapes in the Greenwich World Heritage site

Located 21,000 light-years away, M13 in Hercules is the finest globular cluster north of the celestial equator. The cluster resides on the west side of the Hercules Keystone, about two-thirds of the way from 2nd-magnitude Zeta ([xi]) Herculis to 3.5-magnitude Eta ([eta]) Herculis.

July: planets come and go each year, but globular star clusters return on cue every summer

See if you can feel the exact moment when the sun pulls even with the celestial equator, the imaginary line running from the equator into space.

SPRING SEDUCES LOVE BIRDS

In a fantasy photo-montage called Physics Illustrated, Caprice holds up the world for inspection, rides a crescent moon and sits astride the celestial equator.

Moon dream Caprice; Fantasy team for new mag

From the vantage point of the gate at sundown, the sun appears to descend into a narrow slot in the middle of the temple roof on the first day of fall and first day of spring - the two days the sun is directly on the celestial equator. By running some calculations, he determined that the sun descends into the south corner of the temple roof on the first day of winter (when the sun is at its southernmost point) and into the north corner of the roof on the first day of summer (when the sun is at its northernmost point).

Mexican ruin was solar observatory

"We had been working some calibration stars near the celestial equator, and I decided to swing the telescope to the zenith to obtain minimum background light and check performance in darker backgrounds.

Low-Light-Level Cameras Now Bring Heavenly Happenings Down to Earth

declination The angular distance above (positive) or below (negative) the celestial equator. One of the coordinates, with right ascension, that defines the position of a celestial object.

Glossary

Philippine nights will be longer thereafter as the sun moves below the celestial equator towards the southern hemisphere, PAGASA said.

Day and night will have equal length on Sept. 23 -- PAGASA