JUNTEN Astronomical Ring Men Women Armillary Sphere Ring for Couple Lovers Foldable Cosmic Finger Rings, Size 5-12

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The armillary sphere is commonly used in heraldry and vexillology, being mainly known as a symbol associated with Portugal, the Portuguese Empire and the Portuguese discoveries. Aterini, B.: Geometric instruments for the orientation and measurement: the astrolabes. In: Advances in Historical Studies (AHS), 8, 58–78. Springer (2019b). http://www.scirp.org/journal/ahs. https://doi.org/10.4236/ahs.2019.81004

Each of the signs of the Zodiac is engraved upon the ecliptic ring, which is also calibrated with a calendar scale enabling the instrument to be used to model the apparent motion of the Sun and the stars at any time of the year. The instrument could be used not only to model the movements and relative geometry of the heavens, but to carry out all sorts of calculations, such as the times of sunrise and sunset, the length of a day, and the altitude of the Sun or stars. Christopher Cullen, "Joseph Needham on Chinese Astronomy", Past and Present, No. 87 (May, 1980), pp. 39–53 (45) Further information: Planetarium and Antikythera mechanism Ptolemy with an armillary sphere model, by Joos van Ghent and Pedro Berruguete, 1476, Louvre, Paris In Renaissance Europe, the armillary sphere was amongst the first complex mechanical devices. Public figures often had their portraits painted showing them with one hand on an armillary sphere which represented the height of wisdom and knowledge. 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.About it rotate a set of rings representing the heavens – the celestial sphere – with one complete revolution approximating 24 hours. Tropic of Capricorn: This small circle (also called the Southern Tropic) forms the southernmost latitude on earth at which the noontime sun can cross the zenith. This occurs around Dec 21 — and is called the winter solstice in the northern hemisphere. A corresponding circle, also called the Tropic of Capricorn, is formed by the projection of the earth’s Tropic of Capricorn onto the celestial sphere. In ancient times, the sun passed through the zodiacal constellation of Capricornus at this time of year — thus its name Capricorn. The word “tropic” derives from the Greek word meaning turn — referring to the point on the sky where the sun changes direction and begins moving north as summer approaches in the northern hemisphere. Today, while precession (the wobble of the earth on its axis) has shifted the winter solstice into the constellational of Sagittarius, the solstitial sun remains in the astrological sign of Capricorn, which is unaffected by precession. The Tropic of Capricorn is currently at latitude 23 o 26.2’ S (23.44° S). Like the obliquity, the latitude of the Tropic of Capricorn varies from22.1 o S and 24.5 o Sover about 41,000 years. The Tropic of Capricorn is moving north toward the equator at about 50 feet per year.

The Arctic Circle E, and the Antarctic Circle F, each 23 1⁄ 2 degrees from its respective pole at N and S. The Sphere was not included in the photographic inventory of Griffiths' collection in 1930 so may have been acquired after that date. Its earlier provenance is unknown.Kern, Ralf: Wissenschaftliche Instrumente in ihrer Zeit. Vom 15. – 19. Jahrhundert. Verlag der Buchhandlung Walther König 2010, ISBN 978-3-86560-772-0 armillary sphere, early astronomical device for representing the great circles of the heavens, including in the most elaborate instruments the horizon, meridian, Equator, tropics, polar circles, and an ecliptic hoop. The sphere is a skeleton celestial globe, with circles divided into degrees for angular measurement. In the 17th and 18th centuries such models—either suspended, rested on a stand, or affixed to a handle—were used to show the difference between the Ptolemaic theory of a central Earth and the Copernican theory of a central Sun. Armillary sphere rings like the ones in the British Museum’s collection and the Swedish Historical Museum (top) serve a more benign purpose. Folded together, the two-part outer hoop and three interior hoops give the illusion of a simple gold band. Slipped off the wearer’s finger, they can fan out into a physical model of celestial longitude and latitude. The armillary sphere was reintroduced in the national arms and in the national Flag of Portugal in 1911. Lindberg, David C.; Shank, Michael H. (7 October 2013). The Cambridge History of Science: Volume 2, Medieval Science. Cambridge University Press. p.173. ISBN 978-1-316-02547-5 . Retrieved 15 May 2018.

Savage-Smith, Emilie (1985), Islamicate Celestial Globes: Their History, Construction, and Use, Smithsonian Institution Press, Washington, D.C. Dirk L. Couprie, Robert Hahn, Gerard Naddaf: Anaximander in Context: New Studies in the Origins of Greek Philosophy, 2003, ISBN 978-0-7914-5537-1, p. 179

First ever Heritage Flame lit at Stoke Mandeville in a historic moment for Paralympic Movement". www.paralympic.org. 3 January 2014.

It is believed that the Greek astronomer Hipparchus invented the armillary sphere around 200BC, to decipher how the heavens and stars moved around the earth. His sphere had a ball representing the earth in the centre, and four overlapping rings circling the globe. Zodiac: a band 18 o wide that is centered on the ecliptic. The zodiac comes from the Greek word for "circle of animals" that form the various constellation of stars in the eclilptic. The constellation of animals aries (the ram), taurus (the bull), cancer (the crab), leo (the lion), scorpius (the scorpion), and capricornus (the capricorn) were named at least a thousand years before by Babylonian and Chaldean astronomers. Since Roman times we also have constellation of libra (scales) and the representation of people in the form of aquarius (the water carrier), gemini (the twins), virgo (the virgin), and sagittarius (the archer).Historians disagree about the origin and the use of demonstrational armillary spheres, partly because the available evidence is difficult to interpret.