The aberration of light ( also referred to as astronomical aberration or stellar aberration ) is an astronomical phenomenon which produces an apparent motion of celestial objects about their real locations.

The idea that immediately suggested itself was that the star's declination varied because of short-term changes in the orientation of the Earth's axis relative to the celestial sphere – a phenomenon known as nutation.

While most WIMP models indicate that a large enough number of WIMPs would be captured in large celestial bodies for these experiments to succeed, it remains possible that these models are either incorrect or only explain part of the dark matter phenomenon.

Most of the information used by astronomers is gathered by remote observation, although some laboratory reproduction of celestial phenomenon has been performed ( such as the molecular chemistry of the interstellar medium ).

While the origins of the study of celestial features and phenomenon can be traced back to antiquity, the scientific methodology of this field began to develop in the middle of the 17th century.

Because of a phenomenon known as the precession of the equinoxes, the poles trace out circles on the celestial sphere, with a period of about 25, 700 years.

The phenomenon of day and night is due to the rotation of a celestial body about its axis, creating the illusion of the sun rising and setting.

The so-called " Sun Dog Painting " ( Vädersolstavlan ) depicting Stockholm in 1535 and the celestial phenomenon at the time interpreted as an ominous presage

Strange phenomenon on 17 November 1882, observed and described by Maunder in The Observatory ( astronomy ) | The Observatory, June 1883 ( pp. 192-193 ) and April 1916 ( pp. 213-215 ), which he termed an " auroral beam " and " a strange celestial visitor.

The word " astral " means " of the stars ", thus the astral plane, consisting of the celestial spheres, is held to be an astrological phenomenon: " The whole of the astral portion of our earth and of the physical planets, together with the purely astral planets of our System, make up collectively the astral body of the Solar Logos ".

A celestial event is an astronomical phenomenon of interest that involves one or more celestial bodies.

In a work entitled De Obitus Leonis, the author, Libuinus, reported an unusual celestial phenomenon which was seen on the day that Leo IX died by a group of pilgrims lead by a certain Albertus, who were in the region of Todi ( Umbria north of Rome ).

The text pictures every man hiding in the rocks of the mountains during a major earthquake to attempt to hide from God's wrath, while celestial phenomenon turns the moon blood red and the sun dark.

Matthew 24: 29-31 mentions the same event, yet it places the celestial phenomenon as occurring after the " tribulation of those days ".

* Analemma, the curve traced out by a celestial body over the course of a year on the celestial sphere of another body ; a phenomenon that may be used to determine the time of year

Thus, circular motion is itself one of the essential characteristics of completely perfect celestial existence.

An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.

Amateur astronomy is usually associated with viewing the night sky when most celestial objects and events are visible, but sometimes amateur astronomers also operate during the day for events such as sunspots and solar eclipses.

Among the neo-Platonists and eventually their Christian interpreters, Aphrodite Ourania figures as the celestial Aphrodite, representing the love of body and soul, while Aphrodite Pandemos is associated with mere physical love.

Astrometry is the branch of astronomy that involves precise measurements of the positions and movements of stars and other celestial bodies.

Apart from the fundamental function of providing astronomers with a reference frame to report their observations in, astrometry is also fundamental for fields like celestial mechanics, stellar dynamics and galactic astronomy.

In astronomy, a given point on the celestial sphere ( that is, the apparent position of an astronomical object ) can be identified using any of several astronomical coordinate systems, where the references vary according to the particular system.

These measured positions are then compared with those calculated by the laws of celestial mechanics: an assembly of calculated positions is often referred to as an ephemeris, in which distances are commonly calculated in astronomical units.

Having concluded that everything in the world is composed of air, Anaximenes then used his theory to devise a scheme explaining the origins and nature of the earth as well as of the surrounding celestial bodies.

152-153 .</ ref > The moon and sun are likewise considered to be flat and floating on streams of air, and when the sun sets it does not pass under the earth but is merely obscured by higher parts of the earth as it circles around and becomes more distant ; the motion of the sun and the other celestial bodies around the earth is likened by Anaximenes to the way that a cap may be turned around the head .< ref > Fairbanks, Arthur.

The apparent magnitude ( m ) of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere.

Absolute magnitude ( also known as absolute visual magnitude when measured in the standard V photometric band ) is the measure of a celestial object's intrinsic brightness.

In astronomy, to derive absolute magnitude from the observed apparent magnitude of a celestial object its value is corrected from distance to its observer.

Western astrology is founded on the movements and relative positions of celestial bodies such as the Sun, Moon, planets, which are analyzed by their movement through signs of the zodiac ( spatial divisions of the ecliptic ) and by their aspects ( angles ) relative to one another.

In contrast, stellar aberration is independent of the distance of a celestial object from the observer, and depends only on the observer's instantaneous transverse velocity in certain frame of reference, at the moment of observation.

According to the special theory of relativity, the aberration looks as a transform of the celestial sphere due to different frames of reference and is virtually a special case of velocity addition, namely one of the light beam and frames ' relative velocity v. The formula from relativistic aberration can be simplified to

Arcturus (; α Boo, α Boötis, Alpha Boötis ) is the brightest star in the constellation Boötes and in fact the northern celestial hemisphere.

Arcturus is visible from both hemispheres in the sky, as it is located less than 20 degrees north of the celestial equator.

For approximately two to three weeks on either side of November 30, Antares is not visible in the night sky, because it is near conjunction with the Sun ; this period of invisibility is longer in the Northern Hemisphere than in the Southern Hemisphere, since the star's declination is significantly south of the celestial equator.

The discoid shapes of sun and moon were also felt to indicate the shape of celestial things.

* Atlas ( mythology ), a Titan who bore the spheres of the heavens ; inspiring the widely used image of a man carrying a celestial sphere on his back or shoulders ( also known as Atlas Telamon or " enduring Atlas ")

He also translated many homilies of St. John Chrysostom ; the treatise of the Pseudo-Dionysius the Areopagite on the celestial hierarchy ; St.

Furthermore, epsilon Antliae, eta Antliae, and theta Antliae were incorporated into the celestial temple, which also contained stars from modern Pyxis.

It also included “ information such as weather forecasts, farmers ' planting dates, astronomical information, and tide tables, Astronomical data and various statistics, such as the times of the rising and setting of the sun and moon, eclipses, hours of full tide, stated festivals of churches, terms of courts, lists of all types, timelines, and more .” Mather had within the text of the Almanac the positions and motions of these celestial bodies, which he must have calculated by hand.

A corona is a type of plasma " atmosphere " of the Sun or other celestial body, extending millions of kilometers into space, most easily seen during a total solar eclipse, but also observable in a coronagraph.

The ecliptic is the apparent path of the Sun on the celestial sphere as seen from the Earth's center, and also the plane of this path, which is coplanar with the orbit of the Earth around the Sun.

The crossing from south to north is known as the vernal equinox, also known as the first point of Aries and the ascending node of the ecliptic on the celestial equator.

Geology can also refer generally to the study of the solid features of any celestial body ( such as the geology of the Moon or Mars ).

Shen's contemporary Su Song ( 1020 – 1101 ) was also a polymath and astronomer responsible for the creation of celestial atlas of star maps, as well for writing a pharmaceutical treatise with related subjects of botany, zoology, mineralogy, and metallurgy.

Outer space, also simply called space, refers to the relatively empty regions of the universe outside the atmospheres of celestial bodies.

It is also that half of the celestial sphere north of the celestial equator.

Piscis Austrinus ( also known as Piscis Australis ) is a constellation in the southern celestial hemisphere.

Also associated with the Chinese New Year ( or Lunar New Year ), rabbits are also one of the twelve celestial animals in the Chinese Zodiac for the Chinese calendar.

22b, 23a, 49b ), the book of Jewish mysticism and collection of writings on the Torah written by first century tannaic sage Rabbi Shimon Bar Yochai ( Rashbi ), tells of a celestial manifestation, which causes the crowing of the roosters ; known also in the Talmud, is " blessed be He who has given the cock intelligence ,"( Ber.

The concept is also applicable to other planets and celestial bodies.

A sextant can also be used to measure the Lunar distance between the moon and another celestial object ( e. g., star, planet ) in order to determine Greenwich time which is important because it can then be used to determine the longitude.

Like the Davis quadrant ( also called backstaff ), the sextant allows celestial objects to be measured relative to the horizon, rather than relative to the instrument.

Using similar measurements he showed that comets were also not atmospheric phenomena, as previously thought, and must pass through the supposed " immutable " celestial spheres.

In a more general usage in celestial mechanics, the expression ' tidal force ' can refer to a situation in which a body or material ( for example, tidal water, or the Moon ) is mainly under the gravitational influence of a second body ( for example, the Earth ), but is also perturbed by the gravitational effects of a third body ( for example, by the Moon in the case of tidal water, or by the Sun in the case of the Moon ).