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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] |
Optical Telescope
An optical telescope gathers and focus (optics), focuses light mainly from the visible spectrum, visible part of the electromagnetic spectrum, to create a magnification, magnified image for direct visual inspection, to make a photograph, or to collect data through electronic image sensors. There are three primary types of optical telescope : * ''Refracting telescopes'', which use lens (optics), lenses and less commonly also Prism (optics), prisms (dioptrics) * ''Reflecting telescopes'', which use mirrors (catoptrics) * ''Catadioptric system#Catadioptric telescopes, Catadioptric telescopes'', which combine lenses and mirrors An optical telescope's ability to resolve small details is directly related to the diameter (or aperture) of its objective (optics), objective (the primary lens or mirror that collects and focuses the light), and its light-gathering power is related to the area of the objective. The larger the objective, the more light the telescope collects and the finer det ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflecting Telescope
A reflecting telescope (also called a reflector) is a telescope that uses a single or a combination of curved mirrors that reflect light and form an image. The reflecting telescope was invented in the 17th century by Isaac Newton as an alternative to the refracting telescope which, at that time, was a design that suffered from severe chromatic aberration. Although reflecting telescopes produce other types of optical aberrations, it is a design that allows for very large diameter Objective (optics), objectives. Almost all of the major telescopes used in astronomy research are reflectors. Many variant forms are in use and some employ extra optical elements to improve image quality or place the image in a mechanically advantageous position. Since reflecting telescopes use mirrors, the design is sometimes referred to as a catoptrics, catoptric telescope. From the time of Newton to the 1800s, the mirror itself was made of metalusually speculum metal. This type included Newton's first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Telescope
A radio telescope is a specialized antenna (radio), antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency portion of the electromagnetic spectrum, just as optical telescopes are used to make observations in the visible light, visible portion of the spectrum in traditional optical astronomy. Unlike optical telescopes, radio telescopes can be used in the daytime as well as at night. Since astronomical radio sources such as planets, stars, nebulas and galaxy, galaxies are very far away, the radio waves coming from them are extremely weak, so radio telescopes require very large antennas to collect enough radio energy to study them, and extremely sensitive receiving equipment. Radio telescopes are typically large Parabolic antenna, parabolic ("dish") antennas similar to those employed in tracking and communicating with satellites an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refracting Telescope
A refracting telescope (also called a refractor) is a type of optical telescope that uses a lens (optics), lens as its objective (optics), objective to form an image (also referred to a dioptrics, dioptric telescope). The refracting telescope design was originally used in spyglasses and astronomy, astronomical telescopes but is also used for long-focus lens, long-focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece. Refracting telescopes typically have a lens at the front, then a optical train, long tube, then an eyepiece or instrumentation at the rear, where the telescope view comes to focus. Originally, telescopes had an objective of one element, but a century later, tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Telescope
An infrared telescope is a telescope that uses infrared light to detect celestial bodies. Infrared light is one of several types of radiation present in the electromagnetic spectrum. All celestial objects with a temperature above absolute zero emit some form of electromagnetic radiation. In order to study the universe, scientists use several different types of telescopes to detect these different types of emitted radiation in the electromagnetic spectrum. Some of these are gamma ray, x-ray, ultra-violet, regular visible light (optical), as well as infrared telescopes. Leading discoveries There were several key developments that led to the invention of the infrared telescope: * In 1800, William Herschel discovered infrared radiation. * In 1878, Samuel Pierpoint Langley created the first bolometer. This was a very sensitive instrument that could electrically detect incredibly small changes in temperature in the infrared spectrum. * Thomas Edison used an alternative technolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zacharias Janssen
Zacharias Janssen; also Zacharias Jansen or Sacharias Jansen; 1585 – pre-1632) was a Dutch spectacle-maker who lived most of his life in Middelburg. He is associated with the invention of the first optical telescope and/or the first truly compound microscope, but these claims (made 20 years after his death) may be fabrications put forward by his son. Biography Zacharias Janssen was born in The Hague. Local records seem to indicate he was born in 1585 although a date of birth as early as 1580 or as late as 1588 are also given. His parents were Hans MartensSource: a book by Huib J. Zuidervaart which is to be published in the spring of 2008. The in Middelburg has already been shown a first version of this book. (who may have been a peddler) and Maeyken Meertens, both probably from Antwerp, Belgium. He grew up with his sister Sara in Middelburg, at the time the second most important city of the Netherlands. He was known as a "street seller" who was constantly in trouble with ... [...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] |
Galileo Galilei
Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642), commonly referred to as Galileo Galilei ( , , ) or mononymously as Galileo, was an Italian astronomer, physicist and engineer, sometimes described as a polymath. He was born in the city of Pisa, then part of the Duchy of Florence. Galileo has been called the father of observational astronomy, modern-era classical physics, the scientific method, and modern science. Galileo studied speed and velocity, gravity and free fall, the principle of relativity, inertia, projectile motion and also worked in applied science and technology, describing the properties of the pendulum and "hydrostatic balances". He was one of the earliest Renaissance developers of the thermoscope and the inventor of various sector (instrument), military compasses. With an improved telescope he built, he observed the stars of the Milky Way, the phases of Venus, the Galilean moons, four largest satellites of Jupiter, Saturn's r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starry Messenger
''Sidereus Nuncius'' (usually ''Sidereal Messenger'', also ''Starry Messenger'' or ''Sidereal Message'') is a short astronomical treatise (or ''pamphlet'') published in Neo-Latin by Galileo Galilei on March 13, 1610. It was the first published scientific work based on observations made through a telescope, and it contains the results of Galileo's early observations of the imperfect and mountainous Moon, of hundreds of stars not visible to the naked eye in the Milky Way and in certain constellations, and of the Medicean Stars (later Galilean moons) that appeared to be circling Jupiter.Raphael, Renée. ''Sidereus nuncius; or, A Sidereal Message, by Galileo Galilei''. Isis, Vol. 101, No. 3 (September 2010), pp. 644-645. Published by: The University of Chicago Press on behalf of The History of Science Society. The Latin word ''nuncius'' was typically used during this time period to denote ''messenger''; however, it was also (though less frequently) rendered as ''message''. Though t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jacob Metius
Jacob (Jacobus; sometimes James) Metius (after 1571–1628) was a Dutch instrument-maker and a specialist in grinding lenses. He is primarily known for the patent application he made for an optical telescope in October 1608, a few weeks after Hans Lippershey submitted a patent for the same device. He was the brother of the geometer and astronomer Adriaan Metius. Biography Little is known of Jacob Metius other than he lived his life in Alkmaar. His father was Adriaan Anthonisz, a mathematician/map-maker/military engineer and Alkmaar burgomaster, and his brother was Adriaan Metius. Jacob's date of birth was some time after his brother's (1571). He died in Alkmaar, his death date usually given in sources as 1628 although some put it between 1624 and 1631. Invention of the telescope In October 1608, the States General discussed Jacob Metius's patent application for a device for "seeing faraway things as though nearby", consisting of a convex and concave lens in a tube, and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lens
A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), usually arranged along a common axis. Lenses are made from materials such as glass or plastic and are ground, polished, or molded to the required shape. A lens can focus light to form an image, unlike a prism, which refracts light without focusing. Devices that similarly focus or disperse waves and radiation other than visible light are also called "lenses", such as microwave lenses, electron lenses, acoustic lenses, or explosive lenses. Lenses are used in various imaging devices such as telescopes, binoculars, and cameras. They are also used as visual aids in glasses to correct defects of vision such as myopia and hypermetropia. History The word '' lens'' comes from , the Latin name of the lentil (a seed of a lentil p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Lipperhey
Hans Lipperhey ( – buried 29 September 1619), also known as Johann Lippershey or simply Lippershey, was a German- Dutch spectacle-maker. He is commonly associated with the invention of the telescope, because he was the first one who tried to obtain a patent for it. It is, however, unclear if he was the first one to build a telescope. Biography Lipperhey was born in Wesel, now in western Germany, around 1570. He settled in Middelburg, the capital of the province of Zeeland, now in the Netherlands, in 1594, married the same year and became a citizen of Zeeland in 1602. During that time he became a master lens grinder and spectacle maker and established a shop. He remained in Middelburg until his death, in September 1619. Invention of the telescope Hans Lipperhey is known for the earliest written record of a refracting telescope, a patent he filed in 1608. His work with optical devices grew out of his work as a spectacle maker, an industry that had started in Venice and Floren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
