query: when is halley 's comet predicted to be near earth

pos: Halley's Comet Halley's Comet Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 75–76 years. Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and the only naked-eye comet that might 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 returns to the inner Solar System have been observed and recorded by astronomers since at least 240 BC. Clear records of the comet's appearances were made by Chinese, Babylonian, and

neg: Observational history of comets Halley's predicted return date was later refined by a team of three French mathematicians: Alexis Clairaut, Joseph Lalande, and Nicole-Reine Lepaute, who predicted the date of the comet's 1759 perihelion to within one month's accuracy. Halley died before the comet's return; when it returned as predicted, it became known as Halley's Comet (with the latter-day designation of 1P/Halley). The comet next appears in 2061. Among the comets with short enough periods to have been observed several times in the historical record, Halley's Comet is unique in that it is consistently bright enough to be visible to the naked eye while

neg: Halley's Comet faint trans-Neptunian objects. Astronomers are now able to observe the comet at any point in its orbit. The next predicted perihelion of Halley's Comet is 28 July 2061, when it is expected to be better positioned for observation than during the 1985–1986 apparition, as it will be on the same side of the Sun as Earth. It is expected to have an apparent magnitude of −0.3, compared with only +2.1 for the 1986 apparition. It has been calculated that on 9 September 2060, Halley will pass within of Jupiter, and then on 20 August 2061 will pass within of Venus.

neg: International Cometary Explorer being ejected from the Earth-Moon system and into a heliocentric orbit. Its last and closest pass over the Moon, on December 22, 1983, was only above the lunar surface; following this pass, the spacecraft was re-designated as the International Cometary Explorer (ICE). Its new orbit put it ahead of the Earth on a trajectory to intercept comet Giacobini-Zinner. On September 11, 1985, the craft passed through the comet's plasma tail. ICE transited between the Sun and Comet Halley in late March 1986, when other spacecraft were near the comet on their early-March comet rendezvous missions. (This "Halley Armada" included Giotto,

neg: Near-Earth object smaller than about in diameter (i.e. H = 22.0 with assumed albedo of 14%), are not considered PHAs. NASA's catalog of near-Earth objects also includes the approach distances of asteroids and comets (expressed in lunar distances). The first near-Earth objects to be observed by humans were comets. Their extraterrestrial nature was recognised and confirmed only after Tycho Brahe tried to measure the distance of a comet through its parallax in 1577; and the periodicity of some comets was recognised in 1705, when Edmond Halley first published his orbit calculations for the returning object now known as Halley's Comet. The 1758–1759

neg: Edmond Halley Professor of Geometry at the University of Oxford, his theological enemies, John Tillotson and Bishop Stillingfleet having died, and received an honorary degree of doctor of laws in 1710. In 1705, applying historical astronomy methods, he published "Synopsis Astronomia Cometicae", which stated his belief that the comet sightings of 1456, 1531, 1607, and 1682 were of the same comet, which he predicted would return in 1758. Halley did not live to witness the comet's return, but when it did, the comet became generally known as Halley's Comet. By 1706 Halley had learned Arabic and completed the translation started by Edward

neg: Halley's Comet medieval European chroniclers, but were not recognized as reappearances of the same object at the time. The comet's periodicity was first determined in 1705 by English astronomer Edmond Halley, after whom it is now named. During its 1986 apparition, 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 formation. These observations supported a number of longstanding hypotheses about comet construction, particularly Fred Whipple's "dirty snowball" model, which correctly predicted that Halley would be composed of a mixture

neg: Near-Earth object return of Halley's Comet was the first comet appearance predicted in advance. The first near-Earth asteroid to be discovered was 433 Eros in 1898. The asteroid was subject to several observation campaigns, because measurements of its orbit enabled a precise determination of the distance of the Earth from the Sun. In has been said that Lexell's comet of 1770 was the first discovered Near-Earth object. In 1937, asteroid 69230 Hermes was discovered when it passed the Earth at twice the distance of the Moon. Hermes was considered a threat because it was lost after its discovery; thus its orbit and

neg: Halley's Comet third comet past perihelion in 1986 (1986 III); and it was the ninth comet spotted in 1982 (provisional designation 1982i). The perihelion dates of each apparition are shown. The perihelion dates farther from the present are approximate, mainly because of uncertainties in the modelling of non-gravitational effects. Perihelion dates of 1531 and earlier are in the Julian calendar, while perihelion dates 1607 and after are in the Gregorian calendar. Halley's Comet is visible from Earth every 74–79 years. Halley's Comet Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 75–76 years. Halley is

neg: International Halley Watch Infrared Studies, Large Scale Phenomena, Near-Nucleus Studies, Photometry and Polarimetry, Radio Studies, Spectroscopy and Spectrophotometry, Meteor Studies, and Amateur Observations. The IHW also coordinated with the space missions to the comet, Giotto by the European Space Agency and Vega by the Soviet Union and collaborating countries. The collected data were subsequently published as a digital archive on CD-ROMs. International Halley Watch Halley's Comet, named after English astronomer Edmund Halley who first demonstrated its periodicity, returns to the vicinity of the Sun and Earth approximately every 76 years. Since comets are believed to be the most primordial objects in the solar

neg: International Halley Watch International Halley Watch Halley's Comet, named after English astronomer Edmund Halley who first demonstrated its periodicity, returns to the vicinity of the Sun and Earth approximately every 76 years. Since comets are believed to be the most primordial objects in the solar system, their study is of great importance to planetary science. At the time of the 1986 return (technically, "apparition") of the comet, astronomical telescopes and related instrumentation were vastly more sensitive than for any previous apparition. Consequently, the International Halley Watch (IHW) was organized to stimulate, standardize, collect, and archive observations of the comet. The initial plans were

neg: 26P/Grigg–Skjellerup its approach to Comet Halley, but was unable to obtain images as its camera was destroyed during the Halley rendezvous in 1986. In 1972 the comet was discovered to produce a meteor shower, the Pi Puppids, and its current orbit makes them peak around April 23, for observers in the southern hemisphere, best seen when the comet is near perihelion. The 2002 return (expected perihelion around October 8, 2002) was very unfavorable and no observations were reported. The comet nucleus is estimated to be 2.6 kilometers in diameter. The comet is a type locality for the mineral brownleeite. 26P/Grigg–Skjellerup Comet

neg: Comet ISON Comet ISON and the Great Comet of 1680 led to speculation that there might be a connection between them. Further observations of ISON, however, showed that the two comets are not related. When Earth passed near the orbit of Comet ISON on 14–15 January 2014, it was predicted that micron-sized dust particles blown by the Sun's radiation might cause a meteor shower or noctilucent clouds; however, both events were considered unlikely. Because Earth only passed near Comet ISON's orbit, not through the tail, the chances that a meteor shower would occur were slim. In addition, meteor showers from long-period comets

neg: Crab Nebula comet. Messier catalogued it as the first entry in his catalogue of comet-like objects; in 1757, Alexis Clairaut reexamined the calculations of Edmund Halley and predicted the return of Halley's Comet in late 1758. The exact time of the comet's return required the consideration of perturbations to its orbit caused by planets in the Solar System such as Jupiter, which Clairaut and his two colleagues Jérôme Lalande and Nicole-Reine Lepaute carried out more precisely than Halley, finding that the comet should appear in the constellation of Taurus. It is in searching in vain for the comet that Charles Messier found

neg: Biela's Comet years. At the time it was only the third comet known to be periodic, after comets Halley and Encke. The comet was named after Biela, although there was initially some controversy due to a later but independent discovery by Jean-Félix Adolphe Gambart, who also provided the first mathematical proof linking the 1826 and 1805 comets (letters from Biela and Gambart were published in the same issue of the "Astronomische Nachrichten"). A third claim was made by Thomas Clausen, who had independently linked the comets. The comet appeared as predicted during its 1832 apparition, when it was first recovered by John

neg: Halley's Comet to the retrograde orbit, it has one of the highest velocities relative to the Earth of any object in the Solar System. The 1910 passage was at a relative velocity of 70.56 km/s (157,838 mph or 254,016 km/h). Because its orbit comes close to Earth's in two places, Halley is associated with two meteor showers: the Eta Aquariids in early May, and the Orionids in late October. Halley is the parent body to the Orionids. Observations conducted around the time of Halley's appearance in 1986 suggested that the comet could additionally perturb the Eta Aquariids meteor shower, although it might

neg: Naming of comets BC, which was so named because it was observed shortly after the assassination of Julius Caesar and was interpreted as a sign of his deification. Later eponymous comets were named after the astronomer(s) who conducted detailed investigations on them, or later those who discovered the comet. After Edmond Halley demonstrated that the comets of 1531, 1607, and 1682 were the same body and successfully predicted its return in 1759, that comet became known as Halley's Comet. Similarly, the second and third known periodic comets, Encke's Comet and Biela's Comet, were named after the astronomers who calculated their orbits rather than

neg: C/2011 L4 C/2011 L4 had a "slowdown event" when it was 3.6 AU from the Sun at a magnitude 5.6. The brightness increase rate decreased and the estimated magnitude at perihelion was predicted as +3.5. Comet Halley would be magnitude −1.0 at the same perihelion distance. The same study concluded that C/2011 L4 is very young and belongs to the class of "baby comets" (i.e. those with a photometric age of less than 4 comet years). When C/2011 L4 reached perihelion in March 2013, the actual peak magnitude turned out to be around +1, as estimated by various observers all over the

neg: Halley's Comet Mark Twain" was inspired by the quotation. Halley's 1910 apparition is distinct from the Great Daylight Comet of 1910, which surpassed Halley in brilliance and was actually visible in broad daylight for a short period, approximately four months before Halley made its appearance. Halley's 1986 apparition was the least favourable on record. The comet and Earth were on opposite sides of the Sun in February 1986, creating the worst viewing circumstances for Earth observers for the last 2,000 years. Halley's closest approach was 0.42 AU. Additionally, with increased light pollution from urbanization, many people failed to even see the comet.

neg: Halley's Comet In 2134, Halley is expected to pass within of Earth. Its apparent magnitude is expected to be −2.0. Halley's calculations enabled the comet's earlier appearances to be found in the historical record. The following table sets out the astronomical designations for every apparition of Halley's Comet from 240 BC, the earliest documented widespread sighting. For example, "1P/1982 U1, 1986 III, 1982i" indicates that for the perihelion in 1986, Halley was the first period comet known (designated 1P) and this apparition was the first seen in half-month U (the second half of October) in 1982 (giving 1P/1982 U1); it was the

neg: Comet planet occurred in July 1994 when Comet Shoemaker–Levy 9 broke up into pieces and collided with Jupiter. The names given to comets have followed several different conventions over the past two centuries. Prior to the early 20th century, most comets were simply referred to by the year when they appeared, sometimes with additional adjectives for particularly bright comets; thus, the "Great Comet of 1680", the "Great Comet of 1882", and the "Great January Comet of 1910". After Edmund Halley demonstrated that the comets of 1531, 1607, and 1682 were the same body and successfully predicted its return in 1759 by

neg: Halley's Comet for the man who defeated him, William the Conqueror. The comet is represented on the Bayeux Tapestry and described in the tituli as a star. Surviving accounts from the period describe it as appearing to be four times the size of Venus and shining with a light equal to a quarter of that of the Moon. Halley came within 0.10 AU of Earth at that time. This appearance of the comet is also noted in the "Anglo-Saxon Chronicle". Eilmer of Malmesbury may have seen Halley previously in 989, as he wrote of it in 1066: "You've come, have you? ...

neg: Halley (song) Earth. This comet only can be seen from Earth every 76 years, and could be seen in 1986, named after the astronomer Edmond Halley. It was succeeded as Turkish representative at the 1987 contest by Seyyal Taner & Grup Lokomotif with "Şarkım Sevgi Üstüne". This article was based on information from: Diggiloo net Halley (song) "Halley" was the Turkish entrant to the Eurovision Song Contest 1986 in Bergen, Norway. It was sung by Klips ve Onlar in Turkish. On the night of the final, the song performed in the eighth position (following Netherlands's Frizzle Sizzle singing "Alles heeft ritme" and

neg: 12P/Pons–Brooks 12P/Pons–Brooks 12P/Pons–Brooks is a periodic comet with an orbital period of 71 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). Its next closest approach to Earth is in 2024. As of December 2015 12P/Pons–Brooks has not been identified with any meteor-shower streams. A comet was observed from Korea from 10 April to June 1313 CE. Over in China, "in the reign of Jin Tsung, the 2nd year of the epoch Hwang King, 3rd moon, day Ting Wei, a comet appeared in the eastern part of S. D. Tsing". This date

neg: Halley's Comet (video game) middle of the 21st century. The armies of Lord Halley are launching attacks on planet Earth using Halley's Comet as the spearhead of the attack. The player represents the last chance for Earth piloting a craft specially developed to engage the enemy hordes. The game has six long stages set in locations in space such as, above planets, inside enemy vessels or in asteroid fields. There is always a big boss at the end of each stage each with its own weakness. There are power-ups, which can be picked up along the way when the player shoots particular asteroids or

neg: History of physics the end of the century analytical treatments were rigorous enough to verify the stability of the solar system solely on the basis of Newton's laws without reference to divine intervention—even as deterministic treatments of systems as simple as the three body problem in gravitation remained intractable. In 1705, Edmond Halley predicted the periodicity of Halley's Comet, William Herschel discovered Uranus in 1781, and Henry Cavendish measured the gravitational constant and determined the mass of the Earth in 1798. In 1783, John Michell suggested that some objects might be so massive that not even light could escape from them. In 1739,

neg: Historical comet observations in China may have been Halley, but there is insufficient information to be sure. The most accurate records of Halley begin in 12 BC. In 1843 engineer and sinologist Édouard Biot translated Chinese records of comets. Astronomer John Russell Hind observed that past apparitions of Halley back to 12 BC in most cases could be matched to these Chinese records. A computer calculation of the past orbits of Halley using numerical integration could not continue past 837 AD because a very close approach to Earth made calculation of orbits prior to that too inaccurate. The researchers had started with accurate European measurements

neg: 13P/Olbers will be closest to the Earth on January 10, 2094 when it passes at a distance of 0.756 AU. There is some speculation that 13P/Olbers has an associated meteor shower on Mars coming from the direction of Beta Canis Major. 13P/Olbers 13P/Olbers is a periodic comet with an orbital period of 69 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). Heinrich Wilhelm Matthias Olbers (Bremen) discovered the comet on March 6, 1815. Its orbit was first computed by Carl Friedrich Gauss on March 31, Friedrich Bessel calculated an orbital period

neg: Christian Gärtner Christian Gärtner Christian Gärtner (6 May 1705 – 31 December 1782) was a German telescope maker and astronomer, noted for his observation of the 1758 return of Halley's Comet. Gärtner was born at Tolkewitz near Dresden and even as a child had a passion for the stars. He earned his living as a cloth-bleacher and spent his income on astronomical equipment and books. Later, he learned to grind his own lenses and manufactured and sold telescopes. In December 1758 (simultaneously with Johann Georg Palitzsch) Gärtner observed the return of Halley's Comet, predicted by Edmond Halley in 1705. Gärtner died a

neg: Yrjö Väisälä whom an asteroid 1548 Palomaa was named. For this reason the Palomar Mountain Observatory in California has never had an asteroid bearing its name – the rules for naming asteroids state that the names have to differ from each other with more than one letter. Besides minor planets, he has also discovered 3 comets. The parabolic comet C/1944 H1 observed in 1944 and 1945, as well as the two short period comets, 40P/Vaisala 1, a Jupiter-family comet, and C/1942 EA, a Halley-type and near-Earth comet. Together with Liisi Oterma he co-discovered the Jupiter-family comet 139P/Väisälä-Oterma, which was first classified as

neg: Comet Swift–Tuttle Earth on August 5, 2126. and within from Earth on August 24, 2261. A close encounter with Earth is predicted for the comet's return to the inner Solar System in the year 3044 with the closest approach estimated to be . Another close encounter is predicted for the year 4479, around Sept. 15; the close approach is estimated to be less than 0.05 AU, with a probability of impact of 1 in a million. Subsequent to 4479, the orbital evolution of the comet is more difficult to predict; the probability of Earth impact per orbit is estimated as 2 (0.000002%).

neg: Paolo dal Pozzo Toscanelli Paolo dal Pozzo Toscanelli Paolo dal Pozzo Toscanelli (1397 – 10 May 1482) was an Italian astrologer, mathematician, and cosmographer. Paolo dal Pozzo Toscanelli was born in Florence, the son of the physician Domenico Toscanelli. There is no precise information on his education and background. Gustavo Uzielli in 1894 claimed that Toscanelli studied at the University of Padua, but modern authors consider this pure conjecture. Toscanelli is noted for his observations of comets. Among these was the comet of 1456; only named Halley's comet when Halley predicted its return in 1759. Thanks to his long life, his intelligence and his

neg: Edmond Halley September 1682 observations, he used the laws of motion to compute the periodicity of Halley's Comet in his 1705 "Synopsis of the Astronomy of Comets". It was named after him upon its predicted return in 1758, which he did not live to see. Beginning in 1698, he made sailing expeditions and made observations on the conditions of terrestrial magnetism. In 1718, he discovered the proper motion of the "fixed" stars. Halley was born in Haggerston, in east London. His father, Edmond Halley Sr., came from a Derbyshire family and was a wealthy soap-maker in London. As a child, Halley was

neg: 27P/Crommelin 27P/Crommelin Comet Crommelin, also known as Comet Pons-Coggia-Winnecke-Forbes, is a periodic comet with an orbital period of almost 28 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It is named after the British astronomer Andrew C. D. Crommelin who calculated its orbit in 1930. It is one of only four comets not named after their discoverer(s), the other three being Comets Halley, Encke, and Lexell. The first observation was by Jean-Louis Pons (Marseille, France) on February 23, 1818, he followed the comet until February 27 but was prevented further by

neg: Near-Earth object 1910); and finally as a possible cause of a crater-forming impact that could even cause extinction. The potential of catastrophic impacts by near-Earth comets was recognised as soon as the first orbit calculations provided an understanding of their orbits: in 1694, Edmond Halley presented a theory that Noah's flood in the Bible was caused by a comet impact. Human perception of near-Earth asteroids as benign objects of fascination or killer objects with high risk to human society has ebbed and flowed during the short time that NEAs have been scientifically observed. Scientists have recognised the threat of impacts that create

neg: Johann Franz Encke this time, all the known comets had an orbital period of seventy years and more, with an aphelion far beyond the orbit of Uranus. The most famous comet of this family was Comet Halley with its period of seventy-six years. So the orbit of the comet discovered by Pons was a sensation, because his orbit was found to have a period of 3.3 years, so that the aphelion had to be within the orbit of Jupiter. Encke predicted its return for 1822, but this return was observable only from the southern hemisphere and was seen by Carl Ludwig Christian Rümker

neg: P/2016 BA14 very similar orbits, and studied; it is thought that P/2016 BA14 may have split off from 252P/LINEAR. P/2016 BA14 was bigger than predicted when observed by astronomical radar, it was estimated to be perhaps 125 meters but was about 1 km in diameter. One reason it was hard to predict its size, is because it reflects about 3% of the light, a very low albedo. P/2016 BA14 was said to be the closest approach of Earth by a comet since 1770 when Lexell's Comet is calculated to have passed within 1.4 million miles (2.2 million kilometers) of Earth according to

neg: Arthur Storer his contemporaries with the exception of the Royal Observatory in Greenwich. Arthur Storer Arthur Storer (c. 1648 – 1686) was America's first colonial astronomer. He came to Calvert County, Maryland, from Lincolnshire, England. He was among the first observers to sight and record data about a magnificent comet that passed over Patuxent skies in 1682. Storer's work shows up in a number of Newton's writings. The comet became known as Storer's Comet, until Edmund Halley later predicted the comet's return; thereafter this celestial marvel was known as Halley's Comet. His observations of the great comet of 1680 are mentioned twice

neg: Arthur Storer Arthur Storer Arthur Storer (c. 1648 – 1686) was America's first colonial astronomer. He came to Calvert County, Maryland, from Lincolnshire, England. He was among the first observers to sight and record data about a magnificent comet that passed over Patuxent skies in 1682. Storer's work shows up in a number of Newton's writings. The comet became known as Storer's Comet, until Edmund Halley later predicted the comet's return; thereafter this celestial marvel was known as Halley's Comet. His observations of the great comet of 1680 are mentioned twice in Newton's Philosophiae Naturalis Principia Mathematica. A planetarium bearing Storer's name

neg: 12P/Pons–Brooks coincided with the annual Perseids meteor shower. Even migrating birds cannot be ruled out. Chinese historiography records its first comet around 1500 BCE, although long after the fact; traditionally, this "broom-star" heralded the sweeping-away of the tyrannical Xia dynasty (and its replacement with the Shang). 12P/Pons–Brooks 12P/Pons–Brooks is a periodic comet with an orbital period of 71 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). Its next closest approach to Earth is in 2024. As of December 2015 12P/Pons–Brooks has not been identified with any meteor-shower streams. A comet was

neg: William Whiston creationism and flood geology. It held that the global flood of Noah had been caused by a comet. The work obtained the praise of John Locke, who classed the author among those who, if not adding much to our knowledge, "At least bring some new things to our thoughts." He was an early advocate, along with Edmond Halley, of the periodicity of comets; he also held that comets were responsible for past catastrophes in Earth's history. In 1736, he caused widespread anxiety among London's citizens when he predicted the world would end on 16 October that year because a comet

neg: 23P/Brorsen–Metcalf 22, Michel Giacobini (Paris, France), Ostrovlev (Theodosia, Crimea) and Selavanov (Saint Petersburg). By the end of September 1919 it was confirmed as being the same as Brorsen's comet. 23P/Brorsen–Metcalf 23P/Brorsen–Metcalf is a periodic comet with an orbital period of 70 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It was first discovered by Theodor Brorsen at the Altona Observatory on July 20, 1847, and again by Kaspar Schweizer (Moscow) on August 11, 1847. It was predicted that it would reappear between 1919 and 1922. On August 21, 1919, the comet

neg: 20D/Westphal 20D/Westphal 20D/Westphal was a periodic comet with an orbital period of 61 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It was originally discovered by the German astronomer J. G. Westphal (Göttingen, Germany) on July 24, 1852. It was independently discovered by the American astronomer Christian Heinrich Friedrich Peters (Constantinople) on August 9. The comet was last seen between September 27 and November 26, 1913, first by Pablo T. Delavan (La Plata Astronomical Observatory) and then others. It was predicted to return in 1976 but was never observed, and is

neg: 20D/Westphal now considered a lost comet. 20D/Westphal 20D/Westphal was a periodic comet with an orbital period of 61 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It was originally discovered by the German astronomer J. G. Westphal (Göttingen, Germany) on July 24, 1852. It was independently discovered by the American astronomer Christian Heinrich Friedrich Peters (Constantinople) on August 9. The comet was last seen between September 27 and November 26, 1913, first by Pablo T. Delavan (La Plata Astronomical Observatory) and then others. It was predicted to return in 1976 but

neg: Halley's Comet Having compiled a list of 24 comet observations, he calculated that the orbital elements of a second comet that had appeared in 1682 were nearly the same as those of two comets that had appeared in 1531 (observed by Petrus Apianus) and 1607 (observed by Johannes Kepler). Halley thus concluded that all three comets were, in fact, the same object returning about every 76 years, a period that has since been found to vary between 74–79 years. After a rough estimate of the perturbations the comet would sustain from the gravitational attraction of the planets, he predicted its return for

neg: Halley's Comet as 0.03 AU (3.2 million miles; 5.1 million kilometres) from Earth, by far its closest approach. Its tail may have stretched 60 degrees across the sky. It was recorded by astronomers in China, Japan, Germany, the Byzantine Empire, and the Middle East. In 912, Halley is recorded in the "Annals of Ulster", which state "A dark and rainy year. A comet appeared." In 1066, the comet was seen in England and thought to be an omen: later that year Harold II of England died at the Battle of Hastings; it was a bad omen for Harold, but a good omen

neg: Halley's Comet 1758. While he had personally observed the comet around perihelion in September 1682, Halley died in 1742 before he could observe its predicted return. Halley's prediction of the comet's return proved to be correct, although it was not seen until 25 December 1758, by Johann Georg Palitzsch, a German farmer and amateur astronomer. It did not pass through its perihelion until 13 March 1759, the attraction of Jupiter and Saturn having caused a retardation of 618 days. This effect was computed prior to its return (with a one-month error to 13 April) by a team of three French mathematicians, Alexis

neg: Orionids the activity present in the October night skies. A. S. Herschel produced the first documented record that gave accurate forecasts for the next meteor shower. The Orionid meteor shower is produced by the well known Halley's Comet, which was named after the astronomer Edmund Halley and last passed through the inner solar system in 1986 on its 75- to 76-year orbit. When the comet passes through the solar system, the sun sublimates some of the ice, allowing rock particles to break away from the comet. These particles continue on the comet's trajectory and appear as meteors ("falling stars") when they

neg: Comet the Sun, increasing outgassing rates cause the coma to expand, and the sunlight ionizes gases in the coma. When the solar wind passes through this ion coma, the bow shock appears. The first observations were made in the 1980s and 90s as several spacecraft flew by comets 21P/Giacobini–Zinner, 1P/Halley, and 26P/Grigg–Skjellerup. It was then found that the bow shocks at comets are wider and more gradual than the sharp planetary bow shocks seen at, for example, Earth. These observations were all made near perihelion when the bow shocks already were fully developed. The "Rosetta" spacecraft observed the bow shock at

neg: Halley (song) Halley (song) "Halley" was the Turkish entrant to the Eurovision Song Contest 1986 in Bergen, Norway. It was sung by Klips ve Onlar in Turkish. On the night of the final, the song performed in the eighth position (following Netherlands's Frizzle Sizzle singing "Alles heeft ritme" and preceding Spain's Cadillac with "Valentino"), and at the close of the voting had received 53 points, placing 9th in a field of 20. The song is in praise of the famous Halley comet and the band's joy with it, with the objective to give a good new, Halley comet could be seen in

neg: X/1872 X1 located in a part of the sky which Biela's Comet, last seen in 1852, had been predicted to cross in September, and it was speculated that it might be associated with the comet. As a result, the astronomer Ernst Friedrich Wilhelm Klinkerfues sent a telegram to Pogson, at the Madras Observatory, stating that "Biela touched Earth on 27th: search near Theta Centauri". Pogson began searching for the comet at around 4 a.m. local time on the 3rd, after cloudy weather had hampered observations for two nights. The clouds broke up for a period of around ten minutes, and at 05.15

neg: Peter Jalowiczor Comet Halley taken by an Anglo-Australian 9mm reflector. Jalowiczor's work towards the discovery of exoplanets has been published in the "Astrophysical Journal" in a paper titled "The Lick-Carnegie Survey: Four New Exoplanet Candidates" written with Stefano Meschiari, Gregory P. Laughlin, Steven S. Vogt, R. Paul Butler, Eugenio J. Rivera, and Nader Haghighipour. Jalowiczor has also published in the journal "Monthly Notices of the Royal Astronomical Society" in 1993, in a paper titled "On the variation of cometary coma brightness with comet-Earth distance (the Delta Effect)", authored with David Hughes, Neil McBride, and James Boswell, a research team led by David

neg: 23P/Brorsen–Metcalf 23P/Brorsen–Metcalf 23P/Brorsen–Metcalf is a periodic comet with an orbital period of 70 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It was first discovered by Theodor Brorsen at the Altona Observatory on July 20, 1847, and again by Kaspar Schweizer (Moscow) on August 11, 1847. It was predicted that it would reappear between 1919 and 1922. On August 21, 1919, the comet was recovered by Joel Hastings Metcalf (Camp Idlewild, Vermont, United States) as 8th magnitude. Additional discoveries were made by Edward Barnard (Yerkes Observatory, Wisconsin, United States) on August

neg: Halley's Comet would not fly until late 1990 on STS-35. On 12 February 1991, at a distance of from the Sun, Halley displayed an outburst that lasted for several months, releasing a cloud of dust 300,000 km across. The outburst likely started in December 1990, and then the comet brightened from magnitude 24.3 to magnitude 18.9. Halley was most recently observed in 2003 by three of the Very Large Telescopes at Paranal, Chile, when Halley's magnitude was 28.2. The telescopes observed Halley, at the faintest and farthest any comet has ever been imaged, in order to verify a method for finding very

neg: Bow shocks in astrophysics observations were made in the 1980s and 90s as several spacecraft flew by comets 21P/Giacobini–Zinner, 1P/Halley, and 26P/Grigg–Skjellerup. It was then found that the bow shocks at comets are wider and more gradual than the sharp planetary bow shocks seen at for example Earth. These observations were all made near perihelion when the bow shocks already were fully developed. The Rosetta spacecraft followed comet 67P/Churyumov–Gerasimenko from far out in the solar system, at a heliocentric distance of 3.6 AU, in toward perihelion at 1.24 AU, and back out again. This allowed Rosetta to observe the bow shock as it formed

neg: Edmond Halley Noah's flood might be an account of a cometary impact. However, he was to be vindicated less than three centuries later after the publication of "Und die Sintflut gab es doch" by professors Alexander & Edith Tollmann of the University of Vienna. Their book presents evidence from the geologic record that a comet had split up and then struck the earth in Shoemaker-Levy fashion about 10 millennia ago. In 1698, Halley was given command of the , a pink, so that he could carry out investigations in the South Atlantic into the laws governing the variation of the compass. On

neg: 22P/Kopff plates which he exposed on August 20, 1903, against pre-discovery images of the same region. On August 23, 1903, Kopff concluded it to be a comet with an estimated apparent magnitude of 11. On mid-September 1906, the short-period nature of the comet was recognized by a team headed by Kiel Ebell of the Berkeley Astronomical Department. The comet was missed when it made a return on November 25, 1912, however on June 25, 1919, astronomers recovered the comet. The comet was located less than three days from the predicted position. Over the next several returns to Earth, none were notable

neg: 252P/LINEAR the Discovery Channel Telescope. The body showed a tail, identifying it as a probable comet and then named P/2016 BA14. 252P/LINEAR Comet 252P/LINEAR is a periodic comet and near-Earth object discovered by the LINEAR survey on April 7, 2000. The comet is an Earth-Jupiter family comet, meaning that it passes quite close to both Earth and Jupiter. This causes its orbit to be perturbed frequently on an astronomical timescale. The nominal orbit of 252P/LINEAR [2001] (K102/1) was thrown into the near-Earth region by Jupiter in February 1785, before which it had a perihelion near that of Mars (1774–1785). Prior to

neg: Comet Chasers sue International Rescue for the damages. Scott contacts Alan to collect them. Scott, Francois and his wife jump over bits of the comet until they see the ship get destroyed by the comet. Alan comes in to land near them and he then leaves Thunderbird 3 so he can stand on the comet. The comet shakes and Francois is knocked off and Alan goes to rescue him. Scott sends Alan his space-board. Alan surfs back into Thunderbird 3 and they then take off. When leaving the comet, two of Thunderbird 3's gets hit so they can't return to Earth for

neg: Halley's Comet Originally International Sun-Earth Explorer 3, the probe was renamed and freed from its Lagrangian point location in Earth's orbit to intercept comets 21P/Giacobini-Zinner and Halley. Two Space Shuttle missions—the ill-fated STS-51-L (ended by the "Challenger" disaster) and STS-61-E—were scheduled to observe Halley's Comet from low Earth orbit. STS-51-L carried the Shuttle-Pointed Tool for Astronomy (SPARTAN-203) satellite, also called the Halley's Comet Experiment Deployable (HCED). STS-61-E was a "Columbia" mission scheduled for March 1986, carrying the ASTRO-1 platform to study the comet. Due to the suspension of America's manned space program after the "Challenger" explosion, the mission was canceled, and ASTRO-1

neg: Heart of the Comet on the comet and the subsequent survival struggle against the indigenous lifeforms and the illnesses and infections they cause leads to a breakdown of the expedition crew and the creation of factions based around political beliefs, nationality and genetic differences between the "percells"—genetically enhanced humans—and the "orthos"—unmodified humans. As well as the fighting between these factions, Earth rejects the mission due to fear of contamination from the halleyform life and attempts to destroy the comet and those living upon it. Eventually the mission crew on Halley are forced to accept that they can never return to earth and create a

neg: 41P/Tuttle–Giacobini–Kresák the flare was 10 magnitudes brighter than predicted, reaching easy naked-eye visibility at apparent magnitude 4. However, by June 22, the comet had diminished to about magnitude 11, having produced no flare of note. The comet was not observed during the 2011 unfavorable apparition since the perihelion passage occurred when the comet was on the far side of the Sun. 41P was recovered on November 10, 2016 at apparent magnitude 21 by Pan-STARRS. On April 1, 2017 the comet passed from the Earth. The comet was expected to brighten to around magnitude 7 and be visible in binoculars. 41P/Tuttle–Giacobini–Kresák 41P/Tuttle–Giacobini–Kresák

neg: Comet dust is impenetrable by sunlight and a poor conductor of heat), and slows the loss of gases from the nucleus below. A comet nucleus in an orbit typical of short period comets would quickly decrease its evaporation rate to the point that neither a coma or a tail would be detectable and might appear to astronomers as a low-albedo near-Earth asteroid. Comet dust Comet dust refers to cosmic dust that originates from a comet. Comet dust can provide clues to comets' origin. When the Earth passes through a comet dust trail, it can produce a meteor shower. The models for the

neg: Kreutz sungrazer of Sun's diameter, or about half the distance between the Earth and the Moon. It thus became the first known sungrazing comet. Its perihelion distance was just 1.3 solar radii. Astronomers at the time, including Edmond Halley, speculated that this comet was a return of a bright comet seen close to the Sun in the sky in 1106. 163 years later, the Great Comet of 1843 appeared and also passed extremely close to the Sun. Despite orbital calculations showing that it had a period of several centuries, some astronomers wondered if it was a return of the 1680 comet. A

neg: 252P/LINEAR 252P/LINEAR Comet 252P/LINEAR is a periodic comet and near-Earth object discovered by the LINEAR survey on April 7, 2000. The comet is an Earth-Jupiter family comet, meaning that it passes quite close to both Earth and Jupiter. This causes its orbit to be perturbed frequently on an astronomical timescale. The nominal orbit of 252P/LINEAR [2001] (K102/1) was thrown into the near-Earth region by Jupiter in February 1785, before which it had a perihelion near that of Mars (1774–1785). Prior to this, it had a perihelion in the asteroid belt (1607–1690) and even further before was most likely a Jupiter Trojan.

neg: Eta Aquariids Eta Aquariids The Eta Aquariids are a meteor shower associated with Halley%27s Comet. The shower is visible from about April 19 to about May 28 each year with peak activity on or around May 5. Unlike most major annual meteor showers, there is no sharp peak for this shower, but rather a broad maximum with good rates that last approximately one week centered on May 5. The meteors we currently see as members of the Eta Aquariid shower separated from Halley’s Comet hundreds of years ago. The current orbit of Halley’s Comet does not pass close enough to the Earth

neg: Suisei (spacecraft) after which it would remain in a heliocentric orbit for later use as long as it was viable. "Suisei" began UV observations in November 1985, generating up to 6 images/day. The spacecraft encountered Comet Halley at 151,000 km on sunward side during March 8, 1986, suffering only 2 dust impacts. Fifteen burns of "Suisei"s 3 N motors during the period of April 5–10, 1987, yielded a 65 m/s velocity increase for a 60,000 km Earth gravity assist swingby on August 20, 1992, although the craft was then lost behind the Sun for the summer. The hydrazine fuel was depleted on

neg: 177P/Barnard 177P/Barnard Comet 177P/Barnard, also known as Barnard 2, is a periodic comet with an orbital period of 119 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). The comet, also designated P/2006 M3, was discovered by Edward Emerson Barnard on June 24, 1889, and was re-discovered after 116 years. On July 19, 2006, 177P came within 0.36 AU of the Earth. From late July through September 2006 it was brighter than expected at 8th magnitude in the constellations Hercules and then Draco. Perihelion was August 28, 2006. Of Barnard's other two

neg: Edmond Halley can be seen at St Margaret's Church, Lee Terrace. Halley married Mary Tooke in 1682 and settled in Islington. The couple had three children. There are three pronunciations of the surname "Halley". The most common, both in Great Britain and in the United States, is . This is the personal pronunciation used by most Halleys living in London today. The alternative is often preferred for the man and the comet by those who grew up with rock and roll singer Bill Haley, who called his backing band his "Comets" after the common pronunciation of Halley's Comet in the United States

neg: C/2001 OG108 2003, the comet was estimated to have a mean absolute V magnitude (H) of 13.05 ± 0.10, with an albedo of 0.03, giving an effective radius of 8.9 ± 0.7 km. Using data from Fernandez (2004–2005) JPL lists the comet with an albedo of 0.05 and a diameter of 13.6 ± 1.0 km. This comet probably represents the transition between typical Halley-family/long-period comets and extinct comets. Damocloids have been studied as possible extinct cometary candidates due to the similarity of their orbital parameters with those of Halley-family comets. C/2001 OG108 C/2001 OG108 (LONEOS) is a Halley-type comet with an orbital

neg: Comet the comet" in 1910) and Eudora Welty, to whose life Mary Chapin Carpenter dedicated the song "Halley Came to Jackson". In times past, bright comets often inspired panic and hysteria in the general population, being thought of as bad omens. More recently, during the passage of Halley's Comet in 1910, the Earth passed through the comet's tail, and erroneous newspaper reports inspired a fear that cyanogen in the tail might poison millions, whereas the appearance of Comet Hale–Bopp in 1997 triggered the mass suicide of the Heaven's Gate cult. In science fiction, the impact of comets has been depicted as

neg: Astronomical naming conventions dynamical groups are expected to follow more strictly defined naming schemes. The names given to comets have followed several different conventions over the past two centuries. Before any systematic naming convention was adopted, comets were named in a variety of ways. The first one to be named was "Halley's Comet" (now officially known as Comet Halley), named after Edmond Halley, who had calculated its orbit. Similarly, the second known periodic comet, Comet Encke (formally designated 2P/Encke), was named after the astronomer, Johann Franz Encke, who had calculated its orbit rather than the original discoverer of the comet, Pierre Méchain. Other

neg: 2101 Adonis for these Greek gods. The official naming citation was published by the Minor Planet Center before November 1977 (). Adonis was considered as a possible target for a 6 million km distant flyby by the Vega 2 spacecraft after its 1986 flyby of Halley's comet. In the event Vega 2 didn't have enough fuel post Halley encounter to make the necessary orbital changes for the flyby. 2101 Adonis 2101 Adonis, provisional designation , is an extremely eccentric asteroid, classified as potentially hazardous asteroid and near-Earth object of the Apollo group, approximately 1 kilometer in diameter. Discovered by Eugène Delporte at

neg: Comet Hale–Bopp indicated later that its comet nucleus was 60±20 kilometres in diameter, approximately six times the size of Halley. Its great distance and surprising activity indicated that comet Hale–Bopp might become very bright indeed when it reached perihelion in 1997. However, comet scientists were wary – comets can be extremely unpredictable, and many have large outbursts at great distance only to diminish in brightness later. Comet Kohoutek in 1973 had been touted as a 'comet of the century' and turned out to be unspectacular. Hale–Bopp became visible to the naked eye in May 1996, and although its rate of brightening slowed

neg: Halley's Comet Halley-type comets may have delivered water to Earth in the distant past. Subsequent observations showed Halley's deuterium ratio to be far higher than that found in Earth's oceans, making such comets unlikely sources for Earth's water. "Giotto" provided the first evidence in support of Fred Whipple's "dirty snowball" hypothesis for comet construction; Whipple postulated that comets are icy objects warmed by the Sun as they approach the inner Solar System, causing ices on their surfaces to sublimate (change directly from a solid to a gas), and jets of volatile material to burst outward, creating the coma. "Giotto" showed that this

neg: Stardust (spacecraft) with "Stardust" intercepting comet Tempel 1, a small Solar System body previously visited by "Deep Impact" in 2005. "Stardust" ceased operations in March 2011. On 14 August 2014, scientists announced the identification of possible interstellar dust particles from the "Stardust" capsule returned to Earth in 2006. Beginning in the 1980s, scientists began seeking a dedicated mission to study a comet. During the early 1990s, several missions to study comet Halley became the first successful missions to return close-up data. However, the US cometary mission, Comet Rendezvous Asteroid Flyby, was canceled for budgetary reasons. In the mid-1990s, further support was given

neg: Meteor shower balanced in that the slower descent means that Martian meteors have more time in which to ablate. On March 7, 2004, the panoramic camera on Mars Exploration Rover "Spirit" recorded a streak which is now believed to have been caused by a meteor from a Martian meteor shower associated with comet 114P/Wiseman-Skiff. A strong display from this shower was expected on December 20, 2007. Other showers speculated about are a "Lambda Geminid" shower associated with the Eta Aquariids of Earth ("i.e.", both associated with Comet 1P/Halley), a "Beta Canis Major" shower associated with Comet 13P/Olbers, and "Draconids" from 5335 Damocles.

neg: Halley's Comet not be the parent of that shower. Halley is classified as a "periodic" or "short-period comet"; one with an orbit lasting 200 years or less. This contrasts it with long-period comets, whose orbits last for thousands of years. Periodic comets have an average inclination to the ecliptic of only ten degrees, and an orbital period of just 6.5 years, so Halley's orbit is atypical. Most short-period comets (those with orbital periods shorter than 20 years and inclinations of 20–30 degrees or less) are called Jupiter-family comet. Those resembling Halley, with orbital periods of between 20 and 200 years and inclinations

neg: 18D/Perrine–Mrkos Earth. The comet has not been observed during the following perihelion passages: The next predicted perihelion passage would be on 2017 Feb. 26, but the comet is currently considered lost. 18D/Perrine–Mrkos 18D/Perrine–Mrkos is a periodic comet in the Solar System, originally discovered by the American-Argentine astronomer Charles Dillon Perrine (Lick Observatory, California, United States) on December 9, 1896. For some time it was thought to be a fragment of Biela's Comet. It was considered lost after the 1909 appearance, but was rediscovered by the Czech astronomer Antonín Mrkos (Skalnate Pleso Observatory, Slovakia) on October 19, 1955, using ordinary binoculars, it

neg: 209P/LINEAR and about 2.4 km in diameter. The comet has extremely low activity for its size and is probably in the process of evolving into an extinct comet. 209P/LINEAR came to perihelion (closest approach to the Sun) on 6 May 2014. On 29 May 2014 the comet passed from Earth, but only brightened to about apparent magnitude 12. The 2014 Earth approach was the 9th closest known comet approach to Earth. Preliminary results by Esko Lyytinen and Peter Jenniskens, later confirmed by other researchers, predicted 209P/LINEAR might generate the next big meteor shower which would come from the constellation Camelopardalis on

neg: Bisei Spaceguard Center Nakano. Takeshi Urata was also a former member of BATTerS. Bisei Spaceguard Center The Bisei Spaceguard Center (BSGC) is an astronomical observatory located at Bisei-chō, Okayama, Japan. The facility was constructed during 1999–2000, where it since conducts the Bisei Asteroid Tracking Telescope for Rapid Survey or , an astronomical survey that solely tracks asteroids and space debris. BATTeRS has discovered numerous minor planets and the periodic, Halley-type comet and near-Earth object C/2001 W2 (BATTERS). Space debris, along with defunct spaceships, satellites as well as other small objects can present a hazard to operating spacecraft. Built by the Japan Space Forum

neg: Bisei Spaceguard Center Bisei Spaceguard Center The Bisei Spaceguard Center (BSGC) is an astronomical observatory located at Bisei-chō, Okayama, Japan. The facility was constructed during 1999–2000, where it since conducts the Bisei Asteroid Tracking Telescope for Rapid Survey or , an astronomical survey that solely tracks asteroids and space debris. BATTeRS has discovered numerous minor planets and the periodic, Halley-type comet and near-Earth object C/2001 W2 (BATTERS). Space debris, along with defunct spaceships, satellites as well as other small objects can present a hazard to operating spacecraft. Built by the Japan Space Forum (JSF) with contributions by the Japanese Ministry of Education, Culture,

neg: Observational history of comets occurred between 1337 and 1698. Halley noted that three of these, the comets of 1531, 1607, and 1682, had very similar orbital elements, and he was further able to account for the slight differences in their orbits in terms of gravitational perturbation by Jupiter and Saturn. Confident that these three apparitions had been three appearances of the same comet, he predicted that it would appear again in 1758–9. (Earlier, Robert Hooke had identified the comet of 1664 with that of 1618, while Giovanni Domenico Cassini had suspected the identity of the comets of 1577, 1665, and 1680. Both were incorrect.)

neg: 69P/Taylor predicted by N. A. Belyaev and V. V. Emel'yanenko and on January 25, 1977, Charles Kowal (Palomar Observatory, California, United States) found images on photographic plates for December 13, 1976. The comet was recovered for the returns in 1984 and 1990, and in 1998 was observed as magnitude 12 when it passed close by Earth. 69P/Taylor Comet Taylor, is a periodic comet in the solar system, first discovered by Clement J. Taylor (Cape Town, South Africa) on November 24, 1915. George van Biesbroeck and E. E. Barnard (Yerkes Observatory, Wisconsin, United States) observed that the comet was split into two

neg: Halley's Comet a flat disc of icy debris between 30 AU (Neptune's orbit) and 50 AU from the Sun (in the scattered disc). Another point of origin for the Halley-type comets was proposed in 2008, when a trans-Neptunian object with a retrograde orbit similar to Halley's was discovered, , whose orbit takes it from just outside that of Uranus to twice the distance of Pluto. It may be a member of a new population of small Solar System bodies that serves as the source of Halley-type comets. Halley has probably been in its current orbit for 16,000–200,000 years, although it is not

neg: The Halley Project text of a transmission sent from the headquarters of a body known as "P.L.A.N.E.T.": The player starts out from a base on Halley's Comet and must first make his way to Earth, and then back to Halley. As longer and more difficult missions are completed, the player's rank increases from the starting level of Raven through Shrike, Vulture, Darter, Condor, Swift, Nighthawk, Falcon, Eagle, and finally Starbird. A secret mission at the end of the game is accessible by typing in a password mailed by the software company after the player completes the last registered mission and receives a number

neg: 38P/Stephan–Oterma 38P/Stephan–Oterma 38P/Stephan–Oterma (also known as Comet Stephan–Oterma) is a periodic comet with an orbital period of 38 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It was discovered in January 1867, by Jérôme Eugène Coggia at Marseilles Observatory, France. 38P/Stephan–Oterma last came to perihelion on November 10, 2018. It was recovered by Pan-STARRS on June 24, 2017 while 5.3 AU from the Sun. It has perihelion near the orbit of Mars and has aphelion near the orbit of Uranus. Acting like a centaur-hybrid, between the years 1982 and 2067, this

neg: B612 Foundation by the Neptune system. Reitsema is also responsible for several advances in the use of false-color techniques applied to astronomical images. Reitsema was a member of the Halley Multicolour Camera team on the European Space Agency Giotto spacecraft that took close-up images of Comet Halley in 1986. He has been involved in many of NASA's space science missions including the Spitzer Space Telescope, Submillimeter Wave Astronomy Satellite, the New Horizons mission to Pluto and the Kepler Space Observatory project searching for Earth-like planets orbiting distant stars similar to the Sun. Reitsema participated in the ground-based observations of Deep Impact mission

neg: Halley's Comet extending from zero to more than 90 degrees, are called Halley-type comets. , only 75 Halley-type comets have been observed, compared with 511 identified Jupiter-family comets. The orbits of the Halley-type comets suggest that they were originally long-period comets whose orbits were perturbed by the gravity of the giant planets and directed into the inner Solar System. If Halley was once a long-period comet, it is likely to have originated in the Oort cloud, a sphere of cometary bodies that has an inner edge of 20,000–50,000 AU. Conversely the Jupiter-family comets are generally believed to originate in the Kuiper belt,

neg: Space exploration studied from Earth sometimes with centuries-worth of observations, only a few comets have been closely visited. In 1985, the "International Cometary Explorer" conducted the first comet fly-by (21P/Giacobini-Zinner) before joining the Halley Armada studying the famous comet. The "Deep Impact" probe smashed into 9P/Tempel to learn more about its structure and composition and the "Stardust" mission returned samples of another comet's tail. The "Philae" lander successfully landed on Comet Churyumov–Gerasimenko in 2014 as part of the broader "Rosetta" mission. "Hayabusa" was an unmanned spacecraft developed by the Japan Aerospace Exploration Agency to return a sample of material from the small

neg: Comet Arend–Roland comet was already well developed, he predicted that the object would present a prominent display during April in the northern hemisphere. In early December the comet was 2.5 AU from the Sun and 1.7 AU from the Earth. It was in the constellation Pisces until February, when it reached magnitude 7.5–8. During the April perihelion passage, the tail of the comet reached a length of 15° of arc. The appearance of the tail varied, with streamers on April 16 and May 5, and the tail splitting into three beams on April 29. By April 22 the comet also displayed a

neg: Lexell's Comet The comet was also noted by several other astronomers. The comet was observed in Japan. Surviving records identify it as an astronomical and historical phenomenon. It was observed in the Hejaz in Safar 1184 AH (June 1770), where some believed it to be the comet predicted by the poet al-Fasi, portending future events. On July 1, 1770, the comet passed 0.015 astronomical units from Earth, or approximately 6 times the radius of the Moon's orbit. Charles Messier measured the coma as 2° 23' across, around four times the apparent angular size of the Moon. An English astronomer at the time

neg: 55P/Tempel–Tuttle 55P/Tempel–Tuttle 55P/Tempel–Tuttle (commonly known as Comet Tempel–Tuttle) is a periodic comet with an orbital period of 33 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It was independently discovered by Wilhelm Tempel on December 19, 1865, and by Horace Parnell Tuttle on January 6, 1866. It is the parent body of the Leonid meteor shower. In 1699, it was observed by Gottfried Kirch<ref name="C&MS: 55P/Tempel-Tuttle">C&MS: 55P/Tempel-Tuttle</ref> but was not recognized as a periodic comet until the discoveries by Tempel and Tuttle during the 1866 perihelion. In 1933, S. Kanda deduced

neg: Halley's Comet the captains of the ships err." Researchers in 1981 attempting to calculate the past orbits of Halley by numerical integration starting from accurate observations in the seventeenth and eighteenth centuries could not produce accurate results further back than 837 due to a close approach to Earth in that year. It was necessary to use ancient Chinese comet observations to constrain their calculations. Halley's orbital period has varied between 74–79 years since 240 BC. Its orbit around the Sun is highly elliptical, with an orbital eccentricity of 0.967 (with 0 being a circle and 1 being a parabolic trajectory). The perihelion,

neg: Coma (cometary) comets. Space probe Giotto detected hydrogen ions at distance of 7.8 million km away from Halley when it did close flyby of the comet in 1986. A hydrogen gas halo was detected to be 15 times the diameter of Sun (12.5 million miles). This triggered NASA to point the Pioneer Venus mission at the Comet, and it was determined that the Comet emitting 12 tons of water per second. The hydrogen gas emission has not been detected from Earth's surface because those wavelengths are blocked by the atmosphere. The process by which water is broken down into hydrogen and oxygen

neg: Near-Earth object its mission, Rosetta was crashed into the comet′s surface in 2016. Near-Earth object A near-Earth object (NEO) is any small Solar System body whose orbit brings it to proximity with Earth. By convention, a Solar System body is a NEO if its closest approach to the Sun (perihelion) is less than 1.3 astronomical units (AU). If a NEO's orbit crosses the Earth's and the object is larger than across, it is considered a potentially hazardous object (PHO). Most known PHOs and NEOs are asteroids, but a small fraction are comets. There are over 19,000 known near-Earth asteroids (NEAs), over a

neg: Near-Earth object to the Earth. After the comet's 1992 return, when only the two previous returns in 1862 and 1737 have been identified, orbital calculations showed that the comet would pass very close to Earth during its next return in 2126, with an impact within the range of uncertainty. By 1993, even earlier returns (back to at least 188 AD) have been identified, and the new orbital calculation eliminated the impact risk, predicting the comet to pass Earth in 2126 at a distance of 24 million kilometers. In 3044, the comet is expected to pass Earth at less than 1.6 million kilometers.

neg: Halley (film) to be a meteor shower caused by the cosmic dust trail of Halley's Comet. He thought then that it was too much of a coincidence and called the project like the comet. For the director, Halley is also "a symbol for immortality" since it has being known since the beginnings of astronomy and it orbits around the Sun every 75 years. Hofmann says "it is the eternal witness of our history, with its cycles of upswing and decline. The space between each one of its visits is the duration of a human life." The film premiered at the Morelia International

neg: Comet nucleus including a 1-gram fragment that caused a temporary loss of communication with Darmstadt. Halley was calculated to be ejecting three tonnes of material per second from seven jets, causing it to wobble over long time periods. Comet Grigg–Skjellerup's nucleus was visited after Halley, with Giotto approaching 100–200 km. 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

neg: Science in the Age of Enlightenment explaining the motions of heavenly bodies and the consequences of universal gravitation. Among the prominent astronomers of the age was Edmund Halley. In 1705, Halley correctly linked historical descriptions of particularly bright comets to the reappearance of just one, which would later be named Halley’s Comet, based on his computation of the orbits of comets. Halley also changed the theory of the Newtonian universe, which described the fixed stars. When he compared the ancient positions of stars to their contemporary positions, he found that they had shifted. James Bradley, while attempting to document stellar parallax, realized that the unexplained motion