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GNOCE Yellow Gold Rings Astronomical Sphere Ball Ring Sterling Silver Look at Stars Fashion Rings Personality Jewelry Gifts for Lover Women Men

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Since ancient times, astronomers around the world have used models of the sky to make calculations. With the advent of the armillary sphere, stargazers were given a physical model to better visualize the lines of celestial longitude and latitude. Created independently in ancient Greece and ancient China, these armillary spheres consisted of spherical rings centered on either the Earth or the Sun. During the 16th and 17th centuries, these astronomy tools were sized down to become fashionable finger rings that moved just like regular armillary spheres. The Beijing Capital International Airport Terminal 3 features a large armillary sphere metal sculpture as an exhibit of Chinese inventions for international and domestic visitors. Kern, Ralf: Wissenschaftliche Instrumente in ihrer Zeit. Vom 15. – 19. Jahrhundert. Verlag der Buchhandlung Walther König 2010, ISBN 978-3-86560-772-0 The declination ring is moveable, and rotates on pivots set in the meridian ring. An imaginary line connecting these pivots is parallel to the Earth's axis. The declination "ring" of the traveller's sundial above is not a ring at all, but an oblong loop with a slider for setting the season. It can be used as a sun dial to tell time, if the approximate latitude and season is known, or to tell latitude, if the time is known or observed (at solar noon). It may be considered to be a simplified, portable armillary sphere, or a more complex form of astrolabe.

Savage-Smith, Emilie (1985), Islamicate Celestial Globes: Their History, Construction, and Use, Smithsonian Institution Press, Washington, D.C. Art historian Jessica Stewart writes that in the 17th century, rings such as the above specimen were “used by astronomers to study and make calculations. These pieces of jewelry were considered tokens of knowledge. Inscriptions or zodiac symbols were often used as decorative elements on the bands.” In the 17th century, the armillary sphere was used by astronomers to study and make calculations, so to our designers, this sphere was a symbol of knowledge and wisdom. We believe that magical feeling should be given to everyone, so we designed this ring with this sphere concept – so everyone (and anyone) can feel smart and sharp every time they wear this ring. The equatorial ring occupies a plane parallel to the celestial equator, at right angles to the meridian. It is aligned by The Greek astronomer Hipparchus ( c. 190– c. 120 BC) credited Eratosthenes (276–194 BC) as the inventor of the armillary sphere. [11] [12] [13] [14] [15] Names of this device in Greek include ἀστρολάβος astrolabos and κρικωτὴ σφαῖρα krikōtē sphaira "ringed sphere". [16] The English name of this device comes ultimately from the Latin armilla (circle, bracelet), since it has a skeleton made of graduated metal circles linking the poles and representing the equator, the ecliptic, meridians and parallels. Usually a ball representing the Earth or, later, the Sun is placed in its center. It is used to demonstrate the motion of the stars around the Earth. Before the advent of the European telescope in the 17th century, the armillary sphere was the prime instrument of all astronomers in determining celestial positions.Fixed astronomical rings are mounted on a plinth, like armillary spheres, and can be used as sundials.

Brashear, Ronald (May 1999). "Astronomiæ instauratæ mechanica by Tycho Brahe: Introduction". Special Collections Department. Smithsonian Institution Libraries . Retrieved July 11, 2020. In its simplest form, consisting of a ring fixed in the plane of the equator, the armilla is one of the most ancient of astronomical instruments. Slightly developed, it was crossed by another ring fixed in the plane of the meridian. The first was an equinoctial, the second a solstitial armilla. Shadows were used as indices of the sun's positions, in combinations with angular divisions. When several rings or circles were combined representing the great circles of the heavens, the instrument became an armillary sphere. [1]An armillary sphere (variations are known as spherical astrolabe, armilla, or armil) is a model of objects in the sky (on the celestial sphere), consisting of a spherical framework of rings, centered on Earth or the Sun, that represent lines of celestial longitude and latitude and other astronomically important features, such as the ecliptic. As such, it differs from a celestial globe, which is a smooth sphere whose principal purpose is to map the constellations. It was invented separately, in ancient China possibly as early as the 4th century BC and ancient Greece during the 3rd century BC, with later uses in the Islamic world and Medieval Europe. The tropic of Cancer C, touching the ecliptic at the beginning of Cancer in e, and the tropic of Capricorn D, touching the ecliptic at the beginning of Capricorn in f; each 23 1⁄ 2 degrees from the equinoctial circle.

The ecliptic B, which is divided into 12 signs, and each sign into 30 degrees, and also into the months and days of the year; in such a manner, that the degree or point of the ecliptic in which the sun is, on any given day, stands over that day in the circle of months. Enter the fictional world of James Bond, and you’ll find a number of handy dandy spy rings including one that doubles as a camera, and another capable of shattering bulletproof glass with a single twist. Darlington, Oscar G. "Gerbert, the Teacher," The American Historical Review (Volume 52, Number 3, 1947): 456–476. Armillary spheres were among the first complex mechanical devices. Their development led to many improvements in techniques and design of all mechanical devices. Renaissance scientists and public figures often had their portraits painted showing them with one hand on an armillary sphere, which represented the zenith of wisdom and knowledge. The meridian ring is placed vertically, then rotated (relative to the celestial object) until it is parallel to the local north-south line. The whole ring is thus parallel to the circle of longitude passing through the place where the user is standing.The solstitial colure H, passing through the poles of the heaven, and through the solstitial points Cancer and Capricorn, in the ecliptic. Each quarter of the former of these colures is divided into 90 degrees, from the equinoctial to the poles of the world, for showing the declination of the sun, moon, and stars; and each quarter of the latter, from the ecliptic as e and f, to its poles b and d, for showing the latitude of the stars. Christopher Cullen, "Joseph Needham on Chinese Astronomy", Past and Present, No. 87 (May, 1980), pp. 39–53 (45) a b Savage-Smith, Emilie (2017). "Of Making Celestial Globes There Seems No End" (PDF). Bulletin of the Scientific Instrument Society. No. 132: 1–9.

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