Celestial globeCelestial globes show the apparent positions of the stars in the sky. They omit the Sun, Moon, and planets because the positions of these bodies vary relative to those of the stars, but the ecliptic, along which the Sun moves, is indicated. There is an issue regarding the “handedness” of celestial globes. If the globe is constructed so that the stars are in the positions they actually occupy on the imaginary celestial sphere, then the star field will appear reversed on the surface of the globe (all the constellations will appear as their mirror images).
Astronomical clockAn astronomical clock, horologium, or orloj is a clock with special mechanisms and dials to display astronomical information, such as the relative positions of the Sun, Moon, zodiacal constellations, and sometimes major planets. The term is loosely used to refer to any clock that shows, in addition to the time of day, astronomical information. This could include the location of the Sun and Moon in the sky, the age and Lunar phases, the position of the Sun on the ecliptic and the current zodiac sign, the sidereal time, and other astronomical data such as the Moon's nodes for indicating eclipses), or a rotating star map.
Nicolaus CopernicusNicolaus Copernicus (19 February 1473 – 24 May 1543) was a Renaissance polymath, active as a mathematician, astronomer, and Catholic canon, who formulated a model of the universe that placed the Sun rather than Earth at its center. In all likelihood, Copernicus developed his model independently of Aristarchus of Samos, an ancient Greek astronomer who had formulated such a model some eighteen centuries earlier.
Ancient Greek astronomyAncient Greek astronomy is the astronomy written in the Greek language during classical antiquity. Greek astronomy is understood to include the Ancient Greek, Hellenistic, Greco-Roman, and late antique eras. It is not limited geographically to Greece or to ethnic Greeks, as the Greek language had become the language of scholarship throughout the Hellenistic world following the conquests of Alexander. This phase of Greek astronomy is also known as Hellenistic astronomy, while the pre-Hellenistic phase is known as Classical Greek astronomy.
AvempaceAbū Bakr Muḥammad ibn Yaḥyà ibn aṣ-Ṣā’igh at-Tūjībī ibn Bājja (أبو بكر محمد بن يحيى بن الصائغ التجيبي بن باجة), best known by his Latinised name Avempace (ˈeɪvəmpeɪs; 1085 – 1138), was an Andalusian polymath, whose writings include works regarding astronomy, physics, and music, as well as philosophy, medicine, botany, and poetry. He was the author of the Kitāb an-Nabāt ("The Book of Plants"), a popular work on botany, which defined the sex of plants. His philosophical theories influenced the work of Ibn Rushd (Averroes) and Albertus Magnus.
EphemerisIn astronomy and celestial navigation, an ephemeris (pl. ephemerides; ) is a book with tables that gives the trajectory of naturally occurring astronomical objects as well as artificial satellites in the sky, i.e., the position (and possibly velocity) over time. Historically, positions were given as printed tables of values, given at regular intervals of date and time. The calculation of these tables was one of the first applications of mechanical computers. Modern ephemerides are often provided in electronic form.
GlobeA globe is a spherical model of Earth, of some other celestial body, or of the celestial sphere. Globes serve purposes similar to maps, but unlike maps, they do not distort the surface that they portray except to scale it down. A model globe of Earth is called a terrestrial globe. A model globe of the celestial sphere is called a celestial globe. A globe shows details of its subject. A terrestrial globe shows landmasses and water bodies. It might show nations and major cities and the network of latitude and longitude lines.
History of astronomyAstronomy is the oldest of the natural sciences, dating back to antiquity, with its origins in the religious, mythological, cosmological, calendrical, and astrological beliefs and practices of prehistory: vestiges of these are still found in astrology, a discipline long interwoven with public and governmental astronomy. It was not completely separated in Europe (see astrology and astronomy) during the Copernican Revolution starting in 1543. In some cultures, astronomical data was used for astrological prognostication.
Al-KhwarizmiMuḥammad ibn Mūsā al-Khwārizmī (محمد بن موسى الخوارزمي; 780-850), or al-Khwarizmi, was a Persian polymath from Khwarazm, who produced vastly influential works in mathematics, astronomy, and geography. Around 820 CE, he was appointed as the astronomer and head of the library of the House of Wisdom in Baghdad. Al-Khwarizmi's popularizing treatise on algebra (The Compendious Book on Calculation by Completion and Balancing, 813–833 CE) presented the first systematic solution of linear and quadratic equations.
AstrolabeAn astrolabe (ἀστρολάβος astrolábos; ٱلأَسْطُرلاب al-Asṭurlāb; ستارهیاب Setāreyāb) is an astronomical instrument dating back to ancient times. It serves as a star chart and physical model of visible heavenly bodies. Its various functions also make it an elaborate inclinometer and an analog calculation device capable of working out several kinds of problems in astronomy. In its simplest form it is a metal disc with a pattern of wires, cutouts, and perforations that allows a user to calculate astronomical positions precisely.
