|
Astronomical Sextant
In astronomy, sextants are devices depicting a sixth of a circle, used primarily for measuring the position of stars. There are two types of astronomical sextants, mural instruments and frame-based instruments. They are of significant historical importance, but have been replaced over time by transit telescopes, other astrometry techniques, and satellites such as Hipparcos. Mural sextants The first known mural sextant was constructed in Ray, Iran, by Abu-Mahmud al-Khujandi in 994. To measure the obliquity of the ecliptic, al-Khujandī invented a device that he called ''al-Fakhri sextant'' (al-suds al Fakhrī), a reference to his patron, Buwayhid ruler, Fakhr al Dawla (976–997). This instrument was a sixty-degree arc on a wall aligned along a meridian (north–south) line. Al Khujandi's instrument was larger than previous instruments; it had a radius of about twenty meters. Tekeli, Sevim (1958), 'Nasiruddin, Takiyuddin ve Tycho Brahe'nin Rasat Aletlerinin mukayesesi'. ''Ank ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomy
Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest include planets, natural satellite, moons, stars, nebulae, galaxy, galaxies, meteoroids, asteroids, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond atmosphere of Earth, Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Egyptian astronomy, Egyptians, Babylonian astronomy, Babylonians, Greek astronomy, Greeks, Indian astronomy, Indians, Chinese astronomy, Chinese, Maya civilization, M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Summer Solstice
The summer solstice or estival solstice occurs when one of Earth's poles has its maximum tilt toward the Sun. It happens twice yearly, once in each hemisphere ( Northern and Southern). The summer solstice is the day with the longest period of daylight and shortest night of the year in that hemisphere, when the sun is at its highest position in the sky. At either pole there is continuous daylight at the time of its summer solstice. The opposite event is the winter solstice. The summer solstice occurs during the hemisphere's summer. In the Northern Hemisphere, this is the June solstice (20, 21 or 22 June) and in the Southern Hemisphere, this is the December solstice (20, 21, 22 or 23 of December). Since prehistory, the summer solstice has been a significant time of year in many cultures, and has been marked by festivals and rituals. Traditionally, in temperate regions (especially Europe), the summer solstice is seen as the middle of summer and referred to as midsum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tycho Brahe
Tycho Brahe ( ; ; born Tyge Ottesen Brahe, ; 14 December 154624 October 1601), generally called Tycho for short, was a Danish astronomer of the Renaissance, known for his comprehensive and unprecedentedly accurate astronomical observations. He was known during his lifetime as an astronomer, astrologer, and alchemist. He was the last major astronomer before the invention of the telescope. Tycho Brahe has also been described as the greatest pre-telescopic astronomer. In 1572, Tycho noticed a completely SN 1572, new star that was brighter than any star or planet. Astonished by the existence of a star that ought not to have been there, he devoted himself to the creation of ever more accurate instruments of measurement over the next fifteen years (1576–1591). Frederick II of Denmark, King Frederick II granted Tycho an estate on the island of Hven and the money to build Uraniborg, the first large observatory in Christian Europe. He later worked underground at Stjerneborg, where he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equinox
A solar equinox is a moment in time when the Sun appears directly above the equator, rather than to its north or south. On the day of the equinox, the Sun appears to rise directly east and set directly west. This occurs twice each year, around 20 March and 23 September. An equinox is equivalently defined as the time when the plane of Earth's equator passes through the geometric center of the Sun's disk. This is also the moment when Earth's rotation axis is directly perpendicular to the Sun-Earth line, tilting neither toward nor away from the Sun. In modern times, since the Moon (and to a lesser extent the planets) causes Earth's orbit to vary slightly from a perfect ellipse, the equinox is officially defined by the Sun's more regular ecliptic longitude rather than by its declination. The instants of the equinoxes are currently defined to be when the apparent geocentric longitude of the Sun is 0° and 180°. The word is derived from the Latin ', from ' (equal) and ' ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taqi Al-Din Muhammad Ibn Ma'ruf
Taqi ad-Din Muhammad ibn Ma'ruf ash-Shami al-Asadi (; ; 1526–1585) was an Ottoman polymath active in Cairo and Istanbul. He was the author of more than ninety books on a wide variety of subjects, including astronomy, clocks, engineering, mathematics, mechanics, optics, and natural philosophy. In 1574 the Ottoman Sultan Murad III invited Taqi ad-Din to build an observatory in the Ottoman capital, Istanbul. Taqi ad-Din constructed instruments such as an armillary sphere and mechanical clocks that he used to observe the Great Comet of 1577. He also used European celestial and terrestrial globes that were delivered to Istanbul in gift exchanges. His major work from the use of his observatory is titled "The tree of ultimate knowledge n the end of time or the worldin the Kingdom of the Revolving Spheres: The astronomical tables of the King of Kings urad III (''Sidrat al-muntah al-afkar fi malkūt al-falak al-dawār– al-zij al-Shāhinshāhi''). The work was prepared acc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elisabetha Hevelius
Elisabeth Catherina Koopmann-Hevelius (; 17 January 1647 – 22 December 1693) is considered one of the first female astronomers. Originally from Danzig, Poland, she contributed to improve the work and observations done together with her husband Johannes Hevelius. Early life Elisabeth Koopmann was a member of a rich merchant family in the city of Danzig (modern-day Gdańsk, Poland), located in Pomeranian Voivodeship of the Polish–Lithuanian Commonwealth and a member of the trade organization called Hansa. Elisabetha Koopman's parents were Nicholas Koopman (1601–1672) who was a prosperous merchant and Joanna Mennings (or Menninx; 1602–1679). Nicholas and Joanna were married in Amsterdam in 1633. They moved from Amsterdam to Hamburg before moving to Danzig in 1636. It was in this city, largely German-speaking but a part of Poland at the time, that their daughter Elisabeth was born. Personal life Elisabeth was fascinated with astronomy as a child. When she was sixteen, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graduation (instrument)
A graduation is a marking used to indicate points on a visual scale, which can be present on a container, a measuring device, or the axes of a line plot, usually one of many along a line or curve, each in the form of short line segments perpendicular to the line or curve. Often, some of these line segments are longer and marked with a numeral, such as every fifth or tenth graduation. The scale itself can be linear (the graduations are spaced at a constant distance apart) or nonlinear. Linear graduation of a scale occurs mainly (but not exclusively) on straight measuring devices, such as a rule or measuring tape, using units such as inches or millimetres. Graduations can also be spaced at varying spatial intervals, such as when using a logarithmic, for instance on a measuring cup, can vary in scale due to the container's non- cylindrical shape. Graduations along a curve Circular graduations of a scale occur on a circular arc or limb of an instrument. In some cases, non-ci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johannes Hevelius Und Elisabetha Hevelius
Johannes is a Medieval Latin form of the personal name that usually appears as "John" in English language contexts. It is a variant of the Greek and Classical Latin variants (Ιωάννης, '' Ioannes''), itself derived from the Hebrew name '' Yehochanan'', meaning "YHWH is gracious". The name became popular in Northern Europe, especially in Germany because of Christianity. Common German variants for Johannes are ''Johann'', ''Hannes'', '' Hans'' (diminutized to ''Hänschen'' or ''Hänsel'', as known from "''Hansel and Gretel''", a fairy tale by the Grimm brothers), '' Jens'' (from Danish) and '' Jan'' (from Dutch, and found in many countries). In the Netherlands, Johannes was without interruption the most common masculine birth name until 1989. The English equivalent for Johannes is John. In other languages *Joan, Jan, Gjon, Gjin and Gjovalin in Albanian *'' Yoe'' or '' Yohe'', uncommon American form''Dictionary of American Family Names'', Oxford University Press, 2013. *Ya� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telescope
A telescope is a device used to observe distant objects by their emission, Absorption (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects – an optical telescope. Nowadays, the word "telescope" is defined as a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alidade
An alidade () (archaic forms include alhidade, alhidad, alidad) or a turning board is a device that allows one to sight a distant object and use the line of sight to perform a task. This task can be, for example, to Triangulation (surveying), triangulate a scale map on site using a plane table drawing of intersecting lines in the direction of the object from two or more points or to measure the angle and horizontal distance to the object from some reference point's Polar coordinate system, polar measurement. Angles measured can be horizontal, vertical or in any chosen plane. The alidade sighting ruler was originally a part of many types of scientific and astronomical instrument. At one time, some alidades, particularly using Graduation (instrument), circular graduations as on astrolabes, were also called ''diopters''. With modern technology, the name is applied to complete instruments such as the 'plane table alidade'. Origins The word in Arabic (, , ), signifies the same de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sextant
A sextant is a doubly reflecting navigation instrument that measures the angular distance between two visible objects. The primary use of a sextant is to measure the angle between an astronomical object and the horizon for the purposes of celestial navigation. The estimation of this angle, the altitude, is known as ''sighting'' or ''shooting'' the object, or ''taking a sight''. The angle, and the time when it was measured, can be used to calculate a position line on a nautical or aeronautical chart—for example, sighting the Sun at noon or Polaris at night (in the Northern Hemisphere) to estimate latitude (with sight reduction). Sighting the height of a landmark can give a measure of ''distance off'' and, held horizontally, a sextant can measure angles between objects for a position on a chart. A sextant can also be used to measure the lunar distance between the moon and another celestial object (such as a star or planet) in order to determine Greenwich Mean Time and hence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tycho Instrument Sextant 16
Tycho is a masculine given name, a latinization of Greek Τύχων, from the name of Tyche (), the Greek goddess of fortune or luck. The Russian form of the name is '' Tikhon'' (Тихон). People Given name * Tycho Brahe (1546–1601), Danish nobleman and astronomer * Saint Tikhon of Zadonsk (1724–1783), Russian bishop * Tycho van Meer (born 1974), Dutch field hockey striker Surname * Tommy Tycho (1928–2013), Hungarian-Australian pianist, conductor, composer Pseudonym * Tycho (musician) (born 1977) (Scott Hansen), American ambient music artist and producer, also known as ISO50 Astronomy * Tycho (lunar crater) * Tycho Brahe (Martian crater) * The Tycho-1 Catalogue or Tycho-2 Catalogue of stars * SN 1572, a supernova remnant, often called Tycho's supernova * Tycho G, the companion star of SN 1572 * 1677 Tycho Brahe, an asteroid Fiction * Tycho, a desert ranger henchman from the computer game ''Fallout'' * Tycho, a shipboard AI in the computer game ''Marathon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
