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Kepler's Supernova
SN 1604, also known as Kepler's Supernova, Kepler's Nova or Kepler's Star, was a Type Ia supernova that occurred in the Milky Way, in the constellation Ophiuchus. Appearing in 1604, it is the most recent supernova in the Milky Way galaxy to have been unquestionably observed by the naked eye, occurring no farther than 6 kiloparsecs (20,000 light-years) from Earth. Before the adoption of the current naming system for supernovae, it was named for Johannes Kepler, the German astronomer who described it in '' De Stella Nova''. Observation Visible to the naked eye, Kepler's Star was brighter at its peak than any other star in the night sky, with an apparent magnitude of −2.5. It was visible during the day for over three weeks. Records of its sighting exist in European, Chinese, Korean, and Arabic sources. It was the second supernova to be observed in a generation (after SN 1572 seen by Tycho Brahe in Cassiopeia). No further supernovae have since been observed with certaint ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
False-color
False color (or pseudo color) refers to a group of color rendering methods used to display images in color which were recorded in the visible or non-visible parts of the electromagnetic spectrum. A false-color image is an image that depicts an object in colors that differ from those a photograph (a true-color image) would show. In this image, colors have been assigned to three different wavelengths that our eyes cannot normally see. In addition, variants of ''false color'' such as pseudocolor, density slicing, and choropleths are used for information visualization of either data gathered by a single grayscale channel or data not depicting parts of the electromagnetic spectrum (e.g. elevation in relief maps or tissue types in magnetic resonance imaging). Types of color renderings True color The concept behind true color can help in understanding false color. An image is called a ''true-color'' image when it offers a natural color rendition, or when it comes close to i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naked Eye
Naked eye, also called bare eye or unaided eye, is the practice of engaging in visual perception unaided by a magnifying, light-collecting optical instrument, such as a telescope or microscope, or eye protection. Vision corrected to normal acuity using corrective lenses is still considered "naked". In astronomy, the naked eye may be used to observe celestial events and objects visible without equipment, such as conjunctions, passing comets, meteor showers, and the brightest asteroids, including 4 Vesta. Sky lore and various tests demonstrate an impressive variety of phenomena visible to the unaided eye. Basic properties Some basic properties of the human eye are: *Quick autofocus from distances of 25 cm (young people) to 50 cm (most people 50 years and older) to infinity. * Angular resolution: about 1 arcminute, approximately 0.017° or 0.0003 radians, which corresponds to 0.3 m at a 1 km distance. *Field of view (FOV): simultaneous visual perc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S Andromedae
SN 1885A (also S Andromedae) was a supernova in the Andromeda Galaxy, the only one seen in that galaxy so far by astronomers. It was the first supernova ever seen outside the Milky Way, though it was not appreciated at the time how far away it was. It is also known as "Supernova 1885". Discovery The supernova appears to have been seen first on August 17, 1885, by French astronomer Ludovic Gully during a public stargazing event. Gully thought it was scattered moonlight in his telescope and did not follow up on this observation. Irish amateur astronomer Isaac Ward in Belfast claimed to have seen the object on August 19, 1885, but did not immediately publish its existence. The independent detection of the supernova by Ernst Hartwig at Dorpat (Tartu) Observatory in Estonia on August 20, 1885, however, was communicated in a telegram on August 31, 1885, once Hartwig had verified in more ideal circumstances that the feature was not caused by reflected moonlight. The telegram prom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassiopeia (constellation)
Cassiopeia () is a constellation in the northern sky named after the vain queen Cassiopeia, mother of Andromeda, in Greek mythology, who boasted about her unrivaled beauty. Cassiopeia was one of the 48 constellations listed by the 2nd-century Greek astronomer Ptolemy, and it remains one of the 88 modern constellations today. It is easily recognizable due to its distinctive ' W' shape, formed by five bright stars. Cassiopeia is located in the northern sky and from latitudes above 34°N it is visible year-round. In the (sub)tropics it can be seen at its clearest from September to early November, and at low southern, tropical, latitudes of less than 25°S it can be seen, seasonally, low in the North. At magnitude 2.2, Alpha Cassiopeiae, or Schedar, is generally the brightest star in Cassiopeia, though it is occasionally outshone by the variable Gamma Cassiopeiae, which has reached magnitude 1.6. The constellation hosts some of the most luminous stars known, including the ye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tycho Brahe
Tycho Brahe ( ; born Tyge Ottesen Brahe; generally called Tycho (14 December 154624 October 1601) was a Danish astronomer, known for his comprehensive astronomical observations, generally considered to be the most accurate of his time. He was known during his lifetime as an astronomer, astrologer, and alchemist. He was the last major astronomer before the invention of the telescope. An heir to several noble families, Tycho was well-educated. He took an interest in astronomy and in the creation of more accurate instruments of measurement. He worked to combine what he saw as the geometrical benefits of Copernican heliocentrism with the philosophical benefits of the Ptolemaic system, and devised the Tychonic system, his own version of a model of the universe, with the Sun orbiting the Earth, and the planets as orbiting the Sun. In ''De nova stella'' (1573), he refuted the Aristotelian belief in an unchanging celestial realm. His measurements indicated that "new stars" (''stel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler Drawing Of SN 1604
Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws of planetary motion, and his books ''Astronomia nova'', ''Harmonice Mundi'', and ''Epitome Astronomiae Copernicanae''. These works also provided one of the foundations for Newton's theory of universal gravitation. Kepler was a mathematics teacher at a seminary school in Graz, where he became an associate of Prince Hans Ulrich von Eggenberg. Later he became an assistant to the astronomer Tycho Brahe in Prague, and eventually the imperial mathematician to Emperor Rudolf II and his two successors Matthias and Ferdinand II. He also taught mathematics in Linz, and was an adviser to General Wallenstein. Additionally, he did fundamental work in the field of optics, invented an improved version of the refracting (or Keplerian) telescope, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apparent Magnitude
Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's light caused by interstellar dust along the line of sight to the observer. The word ''magnitude'' in astronomy, unless stated otherwise, usually refers to a celestial object's apparent magnitude. The magnitude scale dates back to the ancient Roman astronomer Claudius Ptolemy, whose star catalog listed stars from 1st magnitude (brightest) to 6th magnitude (dimmest). The modern scale was mathematically defined in a way to closely match this historical system. The scale is reverse logarithmic: the brighter an object is, the lower its magnitude number. A difference of 1.0 in magnitude corresponds to a brightness ratio of \sqrt /math>, or about 2.512. For example, a star of magnitude 2.0 is 2.512 times as bright as a star of magnitude 3.0, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Night Sky
The night sky is the nighttime appearance of astronomical object, celestial objects like stars, planets, and the Moon, which are visible in a clear sky between sunset and sunrise, when the Sun is below the horizon. Natural light sources in a night sky include moonlight, starlight, and airglow, depending on location and timing. Aurorae light up the skies above the polar circles. Occasionally, a large coronal mass ejection from the Sun or simply high levels of solar wind may extend the phenomenon toward the Equator. The night sky and studies of it have a historical place in both ancient and modern cultures. In the past, for instance, farmers have used the status of the night sky as a calendar to determine when to agriculture, plant crops. Many cultures have drawn constellations between stars in the sky, using them in association with legends and mythology about their deity, deities. The history of astrology, anciently developed belief of astrology is generally based on the bel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sky, night, but their immense distances from Earth make them appear as fixed stars, fixed points of light. The most prominent stars have been categorised into constellations and asterism (astronomy), asterisms, and many of the brightest stars have proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. The observable universe contains an estimated to stars. Only about 4,000 of these stars are visible to the naked eye, all within the Milky Way galaxy. A star's life star formation, begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. Its stellar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
De Stella Nova
''De Stella Nova in Pede Serpentarii'' (On the New Star in the Foot of the Serpent Handler), generally known as ''De Stella Nova'' was a book written by Johannes Kepler between 1605 and 1606, when the book was published in Prague. Kepler wrote the book following the appearance of the supernova SN 1604, also known as Kepler's Supernova. This star appeared in the constellation Ophiuchus, the Greek (Ὀφιοῦχος Ophioukhos) "serpent-bearer" which is also known in Latin as Serpentarius . The SN 1604 supernova was observable for almost a year, from October 1604 to October 1605. Observation conditions were good, particularly when it was first visible. A conjunction of Jupiter and Mars happened to be taking place near the place where the supernova appeared, meaning that astronomers happened to be looking in its direction. As a result there were many witnesses to its appearance, but Kepler's observations were particularly meticulous. The care he took not only to record his own ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johannes Kepler
Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws of planetary motion, and his books '' Astronomia nova'', '' Harmonice Mundi'', and '' Epitome Astronomiae Copernicanae''. These works also provided one of the foundations for Newton's theory of universal gravitation. Kepler was a mathematics teacher at a seminary school in Graz, where he became an associate of Prince Hans Ulrich von Eggenberg. Later he became an assistant to the astronomer Tycho Brahe in Prague, and eventually the imperial mathematician to Emperor Rudolf II and his two successors Matthias and Ferdinand II. He also taught mathematics in Linz, and was an adviser to General Wallenstein. Additionally, he did fundamental work in the field of optics, invented an improved version of the refracting (or Keplerian) telescop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernova
A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when a white dwarf is triggered into runaway nuclear fusion. The original object, called the ''progenitor'', either collapses to a neutron star or black hole, or is completely destroyed. The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months. Supernovae are more energetic than novae. In Latin, ''nova'' means "new", referring astronomically to what appears to be a temporary new bright star. Adding the prefix "super-" distinguishes supernovae from ordinary novae, which are far less luminous. The word ''supernova'' was coined by Walter Baade and Fritz Zwicky in 1929. The last supernova to be directly observed in the Milky Way was Kepler's Supernova in 1604, ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
