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Great Comet
A great comet is a comet that becomes exceptionally bright. There is no official definition; often the term is attached to comets such as Halley's Comet, which during certain appearances are bright enough to be noticed by casual observers who are not looking for them, and become well known outside the astronomical community. Great comets appear at irregular, unpredictable intervals, on average about once per decade. Although comets are officially named after their discoverers, great comets are sometimes also referred to by the year in which they appeared great, using the formulation "The Great Comet of ...", followed by the year. Causes The vast majority of comets are never bright enough to be seen by the naked eye, and generally pass through the inner Solar System unseen by anyone except astronomers. However, occasionally a comet may brighten to naked eye visibility, and even more rarely it may become as bright as or brighter than the brightest stars. The requirements for thi ...
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Comet Halley
Halley's Comet or Comet Halley, officially designated 1P/Halley, is a List of periodic comets, short-period comet visible from Earth every 75–79 years. Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and thus the only naked-eye comet that can appear twice in a human lifetime. Halley last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061. Halley's periodic returns to the inner Solar System have been observed and recorded by astronomers around the world since at least 240 BC. But it was not until 1705 that the English astronomer Edmond Halley understood that these appearances were reappearances of the same comet. As a result of this discovery, the comet is named after Halley. During its 1986 visit to the inner Solar System, Halley's Comet became the first comet to be observed in detail by spacecraft, providing the first observational data on the structure of a comet nucleus and the mecha ...
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Halley's Comet
Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 75–79 years. Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and thus the only naked-eye comet that can appear twice in a human lifetime. Halley last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061. Halley's periodic returns to the inner Solar System have been observed and recorded by astronomers around the world since at least 240 BC. But it was not until 1705 that the English astronomer Edmond Halley understood that these appearances were reappearances of the same comet. As a result of this discovery, the comet is named after Halley. During its 1986 visit to the inner Solar System, Halley's Comet became the first comet to be observed in detail by spacecraft, providing the first observational data on the structure of a comet nucleus and the mechanism of coma and tail f ...
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Comet
A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit. If sufficiently bright, a comet may be seen from Earth without the aid of a telescope and may subtend an arc of 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures and religions. Comets usually have highly eccentric elliptical orbits, and they have a wide range of orbital periods, ranging from several years to potentially several mill ...
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Great Comet Of 1680
C/1680 V1, also called the Great Comet of 1680, Kirch's Comet, and Newton's Comet, was the first comet discovered by telescope. It was discovered by Gottfried Kirch and was one of the brightest comets of the seventeenth century. Overview The comet was discovered by Gottfried Kirch, a German astronomer, on 14 November 1680 (New Style), in Coburg, and it became one of the brightest comets of the seventeenth century – reputedly visible even in daytime – and was noted for its spectacularly long tail. Passing 0.42 au from Earth on 30 November 1680, it sped around an extremely close perihelion of on 18 December 1680, reaching its peak brightness on 29 December as it swung outward. It was last observed on 19 March 1681. JPL Horizons shows the comet has roughly a barycentric orbital period of years. the comet is about from the Sun. While the Kirch Comet of 1680–1681 was discovered by – and subsequently named for – Gottfried Kirch, credit must also be given to Eusebio Ki ...
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Ephorus
Ephorus of Cyme (; grc-gre, Ἔφορος ὁ Κυμαῖος, ''Ephoros ho Kymaios''; c. 400330 BC) was an ancient Greek historian known for his universal history. Biography Information on his biography is limited. He was born in Cyme, Aeolia, and together with the historian Theopompus was a pupil of Isocrates in rhetoric. He does not seem to have made much progress as a speaker, and at the suggestion of Isocrates himself he took up literary composition and the study of history. According to Plutarch, Ephorus declined Alexander the Great's offer to join him on his Persian campaign as the official historiographer. His son Demophilus followed in his footsteps as a historian. Main works Ephorus' ''magnum opus'' was a set of 29 books recounting a universal history. The whole work, edited by his son Demophilus—who added a 30th book—contained a summary description of the Sacred Wars, along with other narratives from the days of the Heraclids up until the taking of Perint ...
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Cometary Nucleus
The nucleus is the solid, central part of a comet, once termed a ''dirty snowball'' or an ''icy dirtball''. A cometary nucleus is composed of rock, dust, and frozen gases. When heated by the Sun, the gases sublime and produce an atmosphere surrounding the nucleus known as the coma. The force exerted on the coma by the Sun's radiation pressure and solar wind cause an enormous tail to form, which points away from the Sun. A typical comet nucleus has an albedo of 0.04. This is blacker than coal, and may be caused by a covering of dust. Results from the ''Rosetta'' and ''Philae'' spacecraft show that the nucleus of 67P/Churyumov–Gerasimenko has no magnetic field, which suggests that magnetism may not have played a role in the early formation of planetesimals. Further, the ALICE spectrograph on ''Rosetta'' determined that electrons (within above the comet nucleus) produced from photoionization of water molecules by solar radiation, and not photons from the Sun as thought ea ...
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X/1106 C1
X/1106 C1, also known as the Great Comet of 1106, was a great comet that appeared on 2 February 1106, and was observed around the world from the beginning of February through to mid-March. It was recorded by astronomers in Wales, England, Japan, Korea, China and Continental Europe. It was observed to split into many pieces, forming the Great Comet of 1882 and Comet Ikeya–Seki as well as over 4000 small sungrazing comets observed by the SOHO space telescope. It is a member of the Kreutz Group, known as Subfragment I, a split from an earlier large (~150 km) comet that progressively fragmented under the influence of the Sun. Observations Britain A brief note in the Welsh manuscript known as the ''Brut y Tywysogion'' reads: 1106 Yn y vlwydyn honno y gwelat seren anryued y gwelet yn anuon paladyr oheuni yn ol y chefyn ac o prafter colofyn y veint a diruawr oleuat idaw, yn darogan yr hyn a vei rac llaw: kanys Henri, amherawdyr Rufein, gwedy diruawryon vudugolyaetheu a chrefud ...
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Smyth The Great Comet Of 1843
Smyth is an early variant of the common surname Smith commonly found in Ireland.Citation: Bardsley, 1901 Shown below are notable people who share the surname "Smyth". Notable people sharing the Smyth surname Listed here are people who share the 'Smyth' surname, organized by birth year. Families * Smyth baronets, several independently created British hereditary titles * Bowyer-Smyth baronets, holders of a single British hereditary title Smyth disambiguation pages * John Smyth (other) * Richard Smyth (other) * William Smyth (other) Notes Other uses * Smyth County, Virginia References * See also * Smith (other) * Smythe (other) * Smith (surname) Smith is an occupational surname originating in England, Scotland, and Ireland. It is the most prevalent surname in the United Kingdom, the United States, Australia, Canada, and New Zealand, and the fifth most common surname in the Republic of ... {{surname English-la ...
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Winter
Winter is the coldest season of the year in polar and temperate climates. It occurs after autumn and before spring. The tilt of Earth's axis causes seasons; winter occurs when a hemisphere is oriented away from the Sun. Different cultures define different dates as the start of winter, and some use a definition based on weather. When it is winter in the Northern Hemisphere, it is summer in the Southern Hemisphere, and vice versa. In many regions, winter brings snow and freezing temperatures. The moment of winter solstice is when the Sun's elevation with respect to the North or South Pole is at its most negative value; that is, the Sun is at its farthest below the horizon as measured from the pole. The day on which this occurs has the shortest day and the longest night, with day length increasing and night length decreasing as the season progresses after the solstice. The earliest sunset and latest sunrise dates outside the polar regions differ from the date of the winte ...
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Caesar's Comet
Caesar's Comet (also ''Sidus Iulium'' ("Julian Star"); ''Caesaris astrum'' ("Star of Caesar"); Comet Caesar; the Great Comet of 44 BC; numerical designation C/−43 K1) was a seven-day cometary outburst seen in July 44 BC. It was interpreted by Romans as a sign of the deification of recently assassinated dictator, Julius Caesar (100–44 BC). It was perhaps the most famous comet of antiquity. Based on two dubious reports from China (May 30) and Rome (July 23), an infinite number of orbit determinations can fit the observations, but a retrograde orbit is inferred based on available notes.The Comet of 44 B.C. and Caesar's Funeral Games (John T. Ramsey, A. Lewis Lichtp. 125/ref> The comet approached Earth both inbound in mid-May and outbound in early August.Cometography Vol p. 22by Gary W. Kronk It came to perihelion (closest approach to the Sun) on May 25, −43 at a solar distance of about . At perihelion the comet had a solar elongation of 11 degrees and is hypothesized to ha ...
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Von Einem Schrecklichen Vnd Wunderbarlichen Cometen So Sich Den Dienstag Nach Martini Dieses Lauffenden M
The term ''von'' () is used in German language surnames either as a nobiliary particle indicating a noble patrilineality, or as a simple preposition used by commoners that means ''of'' or ''from''. Nobility directories like the ''Almanach de Gotha'' often abbreviate the noble term ''von'' to ''v.'' In medieval or early modern names, the ''von'' particle was at times added to commoners' names; thus, ''Hans von Duisburg'' meant "Hans from he city ofDuisburg". This meaning is preserved in Swiss toponymic surnames and in the Dutch or Afrikaans '' van'', which is a cognate of ''von'' but does not indicate nobility. Usage Germany and Austria The abolition of the monarchies in Germany and Austria in 1919 meant that neither state has a privileged nobility, and both have exclusively republican governments. In Germany, this means that legally ''von'' simply became an ordinary part of the surnames of the people who used it. There are no longer any legal privileges or constraints ass ...
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Great Comet Of 1264
The Great Comet of 1264 (C/1264 N1) was one of the brightest comets on record. It appeared in July 1264 and remained visible to the end of September. It was first seen during the evenings after sunset, but appeared in its greatest splendor in weeks afterward, when it became visible during the mornings in the northeastern sky, with the tail perceived long before the comet itself rose above the horizon. The head of the comet seemed like an obscure and ill-defined star, and the tail passed from this portion of it like expanded flames, stretching forth towards the mid-heavens to a distance of one hundred degrees from the nucleus. The comet of 1264 was described to have been an object of great size and brilliancy. The comet's splendor was greatest at the end of August and the beginning of September. At that time, when the head was just visible above the eastern horizon in the morning sky, the tail stretched out past the mid-heaven towards the west, or was nearly 100° in length. The chr ...
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