Astronomy and related astronomical terms
(the science of the celestial bodies: the sun, the moon, and the planets; the stars and galaxies; and all of the other objects in the universe)
As he raised his cup,
"Thank heavens my business
Is looking up."
2. Apparent displacement of a star from its true position, due to the combined effects of the speed of light and the speed of the earth in orbit around the sun (about 30 kilometers per second or 18.5 miles per second).
The ablation shielding on a re-entry vehicle; such as, the Space Shuttle, is designed to protect against or to minimize such action.
2. A measure of the true or intrinsic brightness of a star as if all stars were the same distance (32.6 light-years) from the observer.
Each element on the periodic chart absorbs energy at specific wavelengths of light which looks like a bar code.
The result is a series of dark bands crossing the spectrum, known as absorption lines.
2. A process in which many smaller bodies congregate together under the action of forces to produce much larger bodies.
Such a force could be, for example, gravitation.
In losing its initial angular momentum, the hot material descends into the black hole, friction causing it to reach temperatures high enough to produce x-rays.
It is by the accretion ring emission that makes it possible for the presence of the black hole to be inferred.
Chondrites are made up of small round granules of extraterrestrial origin found embedded in some meteorites while achondrites are lacking such small granules.
2. The fraction of the solar radiation that is reflected back into space.
3. The ratio of the amount of light reflected from an object in all directions to the amount of incident light.
An albedo of 1.0 corresponds to a perfect reflector.
2. Material that is formed or introduced from somewhere other than the place it is presently found.
It served as the basic guide for Islamic and European astronomers until about the beginning of the 17th century.
It came from a hybrid of Arabic and Greek ("the greatest"); however, Ptolemy's name for it was Mathematike Syntaxis, "The Mathematical Collection" because he believed that its subject, the motions of the heavenly bodies, could be explained in mathematical terms.
The opening chapters present empirical arguments for the basic cosmological framework within which Ptolemy worked. The earth, he argued, is a stationary sphere at the center of a vastly larger celestial sphere that revolves at a perfectly uniform rate around the earth, carrying with it the stars, planets, sun, and moon; thereby, causing their daily risings and settings.
Through the course of a year the sun slowly traces out a great circle, known as the ecliptic, against the rotation of the celestial sphere.
The moon and planets similarly travel backward; hence, the planets were also known as "wandering stars" against the "fixed stars" found in the ecliptic.
The fundamental assumption of the Almagest is that the apparently irregular movements of the heavenly bodies are in reality combinations of regular, uniform, and circular motions.
The Almagest arose as an Arabic corruption of the Greek word for greatest (megiste). It was translated into Arabic about 827 and then from Arabic to Latin in the last half of the 12th century.
Subsequently, the Greek text was circulated widely in Europe, although the Latin translations from Arabic continued to be more influential.