Extractions: < 5o. * Ptolemy still used physical, heavenly spheres and so the universe was finite, with the stars approximately 20000 earth radii away (assuming an earth-moon distance of 59 earth radii - though this model had no set distance scale.) * Even after it was discredited, Ptolemy's model was still in use - because it did predict the locations of the planets rather well.
History Before Christ 120 BC? hipparchus of rhodes (161 BC?122 BC?) explains the pattern of the cosmosin latitude and longitude; and makes triangular measurement of celestial http://www.didyouknow.cd/history/bc.htm
Extractions: H I S T O R Y BC : Before Christ History Time - 1001 BC 8000 BC Invention of the wheel, most likely. With the cultivation of grains in river valleys, the age of agriculture begins. Wine and beer is produced. 7000 BC Use of pottery. 6000 BC Linen is made from the flax plant. 5000 BC Mesopotanian civilisation. Development of irrigation. Cultivation of maize. Use of copper. 4241 BC Earliest recorded date in Egyptian calendar. 4000 BC Meslim, King of Kish, rules Sumeria (Southern Babylonia). Development of plowing and taming of horses. 3760 BC First year of Jewish calendar. 3500 BC First phonetic writing and formation of numbering system by Summerians, who also were among the first to use wagons for carrying goods and people. 3000 BC Building of temples and canals in Sumeria, ruled by Ur-Nina. Fourth Egyptian Dynasty founded by Snefru. The Epic of Gilgamesh, in poetry form, written (One of the oldest works of literature. Fragments of the Epic of Gilgamesh were found on clay tablets in the 19th century in the ancient city of Nineveh. It tells the story of a semidivine king named Gilgamesh who sought immortality. The king was probably based on an historical king of Uruk in Mesopotamia..) 2850 BC Fu-Hi becomes first Emperor of China.
Extractions: Some of the most famous scientists in history were cheats. And at this very moment thousands of researchers are fiddling their results to fit their theories. Yet we persist in thinking that science offers objective truth and ignore that what the scientist discovers is inevitably subjective. Illustrations: Jim Needle The great astronomer of antiquity, this second-century Egyptians theories of the universe held sway for 1,500 years. However, he did most of his observing in the library at Alexandria. Here he calmly lifted the work of an earlier Greek astronomer, Hipparchus of Rhodes. The fraud was not discovered until the nineteenth century when scientists re-examining Ptolemys original data noticed that the Egyptian astronomer had a blind spot for stars clearly visible from Alexandria - but was remarkably well able to see those visible from Rhodes. Galileo Galilei Best known for dropping stones from the leaning tower of Pisa and saying the earth went round the sun, Galileo Galilei was the first to insist on experiment as the only way of discovering truth. But colleagues of the seventeenth-century Italian physicist had considerable difficulty in reproducing some of his results
Malaspina.com - Hipparchus (ca. 190- Ca. 125 BC) The geographical fragments of Hipparchus Harvard Citation. AdditionalBiography University of Virginia MacTutor Entry on hipparchus of rhodes http://www.mala.bc.ca/~mcneil/hippar1.htm
Sophia-L By Subject Aristarchus of Samos and hipparchus of rhodes. David Fideler Wed, 21 Feb 1996200455 GMT. Aristotle s Tyranny. Hrannar Mar Sigurdsson Wed, http://www.uni-heidelberg.de/subject/hd/fak7/hist/o1/logs/sophia/log.started9602
* Meridian - (GIS): Definition Around 50 years later, a greek, hipparchus of rhodes invented a worldwidereferencing system of meridians and paralells that we use to describe earth http://en.mimi.hu/gis/meridian.html
Extractions: Home Menu(0); pozicio('GIS','Meridian') MimiF1("GIS",0); See also: Map Projection Parallel Area ... Equator CreateTd(0) The term " meridian " comes from the Latin meridies, meaning "midday"; the sun crosses a given meridian midway between the times of sunrise and sunset on that meridian callurl('http://en.wikipedia.org/wiki/Meridian_%28geography%29');
Lecture 6: Motions Of The Stars 1718 for three bright stars Sirius, Aldebaran, and Arcturus, by comparinghis measurements of their positions to those of hipparchus of rhodes (300BC). http://www-astronomy.mps.ohio-state.edu/~pogge/Ast162/Unit1/motions.html
Extractions: The great distances to the stars means that their apparent motions across the sky are very small during a human lifetime. Proper Motions Apparent angular motion of nearby stars with respect to more distant stars. These reflect the true motion of the stars relative to the Sun through space. Proper motions are Cumulative The effect of proper motions build up over time... The longer you wait, the greater the apparent angular motion is Modern measurement of proper motions: Example: Consider a star with a proper motion of 0.1 arcsec/year:
Lecture 7: Brightnesses Of Stars Traditional system dating to classical times (hipparchus of rhodes, c. 300BC).Rank stars into 1st, 2nd, 3rd, etc. magnitude. http://www-astronomy.mps.ohio-state.edu/~pogge/Ast162/Unit1/bright.html
Extractions: Stellar Brightness Key Ideas: Apparent Brightness of a star depends upon Inverse Square Law of Brightness How "Bright" is an Object? We must define the "Brightness" of an object quantitatively. Two ways to quantify brightness: Luminosity Luminosity is the total energy output from an object. The Luminosity of a star is a measurement of its total energy production. Apparent Brightness Measure of how bright an object appears to be as seen by a distant observer. What we measure here on earth (an "observable"). Measured in Flux Units Depends on the Distance to the object.
Astronomical Games: June 2001 forward was made by the greatest astronomer of antiquity, hipparchus of rhodes (c . However, Hipparchus wasn t aware of the causes of the anomaly, http://astro.isi.edu/games/kepler.html
Extractions: and ideas are the other. Victor Hugo, A SEMI-RECENT survey [ ] showed that about a quarter of American adults believe that the Sun goes around the Earth. You can imagine the uproar that rose up in educational institutions around the country. (Actually, it was pretty subdued, and if you were of a cynical bent, you could draw some pretty depressing conclusions about what higher education thinks of the American mandatory educational system. But let's not get into that.) How is it possible that so many Americans could believe such a thing? Well, they believe it for the same reason that the ancient Greeks and everyone else up to about the 16th century believed it. All you have to do is look up, and if you have the common sense God granted the garden snail, it is plain to see that the Sun goes around the Earth. After all, astronomers claim the Moon goes around the Earth, and no one laughs at them for that Granted, appearances were not all that mattered to the Greeks. They had their theory, too. Aristotelian physics held that the Earth was all that was base and ignoble, and it therefore sank to the very center of the universe. The celestial objects, howevereverything up in the skywere good and noble, and therefore light and airy, and they all travelled in great circular arcs around the lowly center, maintaining a cordial distance at all times.
Science & Religion BCE actually measured its circumference to within 1%, and hipparchus of rhodesa few years later measured the length of the year to within 5 minutes. http://www.angelfire.com/nb/lt/docs/science-religion.htm
Extractions: [Home] SCIENCE AND RELIGION One day in January 1348 a ship docked in Genoa in Italy, arriving from the Middle East. It brought with it the Black Death - bubonic plague, a disease now well controlled by modern medicine but then, like almost all illness, without cure. It took hold rapidly and spread out in concentric waves over the next 3-4 years across the whole of Europe. Up to 1 in 3 of the whole population of Europe died. Not only could they not cure it: people then had no notion of infection, or of germs or of their spread by rats. They came up with many possible explanations, like putting it down to the influence of the planets drawing foul exhalations from the earth. Almost everyone saw it as a punishment decreed by God, because the 14th century - like all ages in the eyes of religious commentators - was, after all, a uniquely wicked and dissolute age. The poet William Langland said in Piers Plowman : "These pestilences were for pure sin." The best people could do for cures was to fill the house with sweet-smelling flowers and spices, or prescribe medicine concocted from treacle, wine and chopped-up snakes. It was a plague like AIDS today in Africa - beyond control - but worse: it killed people within a few days, and it was beyond all understanding.
A Chronology Of Interpolation 150 BC hipparchus of rhodes uses linear interpolation in the construction oftables of the socalled chord-function (related to the sine function) for http://imagescience.bigr.nl/meijering/research/chronology/
Extractions: It is an extremely useful thing to have knowledge of the true origins of memorable discoveries, especially those that have been found not by accident but by dint of meditation. It is not so much that thereby history may attribute to each man his own discoveries and others should be encouraged to earn like commendation, as that the art of making discoveries should be extended by considering noteworthy examples of it. G. W. Leibniz, Historia et Origo Calculi Differentialis ca. 1714). Translation as in J. M. Child, "Newton and the Art of Discovery", in Isaac Newton 16421727: A Memorial Volume , W. J. Greenstreet (ed.), G. Bell and Sons, London, 1927, pp. 117-129. ca. 300 BC and earlier: Babylonian astronomers use linear and higher-order interpolation to fill gaps in ephemerides of the sun, moon, and the then-known planets, written down in cuneiform tablets as shown here. For explanations and more details, see O. Neugebauer
SGI TPL View (epicycle) HISTORY The geometry of epicycles was perfected by hipparchus of rhodes at sometime around 125 BC, 185 years after the birth of Aristarchus of Samos, http://techpubs.sgi.com/library/tpl/cgi-bin/getdoc.cgi?coll=fw&db=man&fname=/usr
OBSERVATORY - LoveToKnow Article On OBSERVATORY hipparchus of rhodes, the founder of modern astronomy, by repeating observationsmade at Alexandria, discovered the precession of the equinoxes, http://12.1911encyclopedia.org/O/OB/OBSERVATORY.htm
Extractions: OBSERVATORY. Up to a comparatively recent date an " observatory " was a place exclusively devoted to the taking of astronomical observations, although frequently a rough account of the weather was kept. When the progress of terrestrial magnetism and meteorology began to make regular observations necessary, the duty of taking these was often thrown on astronomical observatories, although in some cases separate institutions were created for the purpose. In this article the astronomical observatories will be chiefly considered. Up to about 300 B.C. it can scarcely be said that an observatory existed anywhere, as the crude observations of the heavens then taken were only made by individuals and at intervals, employing the simplest possible apparatus. Thus, according to Strabe. While the necessity of following the sun, moon and planets as regularly as possible increased the daily work of observatories, other branches of astronomy were opened and demanded other observations. Hitherto observations of the fixed stars had been supposed to be of little importance beyond fixing points of comparison for observations of the movable bodies. But when many of the fixed stars were found to be endowed with proper motion, it became necessary to include them among the objects of constant attention, and in their turn the hitherto totally neglected telescopic stars had to be observed with precision, when they were required as comparison stars for comets or minor planets. Thus the field of work for meridian instruments became very considerably enlarged.
Scientific American Digital Browse It was made around 150 BC by hipparchus of rhodes he probably used a tabletopbrass dial. Around 1600 Tycho Brahe, with wallsize circles and metal sights http://www.sciamdigital.com/browse.cfm?ITEMIDCHAR=48C5C38C-433E-4218-A5ED-E12B43
Extractions: Full Review "The Extraordinary Journey of Pytheas the Greek" is somewhat misnamed. Pytheas was an actual person, born Massalia (present day Marseilles), a Greek colony, in the 4th century BCE. His own account of his travels, "On the Ocean," is no longer extant. Cunliffle relies on all that is left of it, that is, in excerpts recorded in the works of such classical writers as Strabo, Pliny the Elder, and a host of others, some well-known, others as almost obscure as Pytheas himself. Pytheas claimed to have sailed to England and "walked the breadth of it." He could not measure longitude, but had a crude way of measuring latitude by measuring the sun's height at noon on the summer solstice (or subtracting the days until the solstice) with a surveying staff called a "gnomon." The idea of parallel lines of latitude would not developed for another couple centuries by one Hipparchus of Rhodes who used Pytheas' measurements in plotting places in the far north. Pytheas also had a crude way of measuring distance by sea using a rule of thumb as to how far a ship could travel per day.
Small Angles And Large Numbers Useful for the Moon, and already known to the ancient Greek In the 2nd centuryBC, hipparchus of rhodes found the distance to the Moon to be 59-67 times http://www.uni-sw.gwdg.de/~derek/ASTR1020/numbers.html
Extractions: Small Angles and Large Numbers The same way positions on the celestial sphere are specified as angles, ``lengths'' and distances between points on the sphere can be measured in angles. ``Areas'' are given in units of solid angles. We are using the degree , denoted as , as unit of angular measure. 360 are a full circle, 90 a right angle One degree is divided into 60 minutes of arc or arcmin . One arcminute is subdivided into 60 seconds of arc or arcsec , analogous to the units of time. Example: The Moon has an angular diameter of , or 30 , or 1800 Right ascension is measured in units of time, i. e. a full circle corresponds to 24 hours . Thus, 1 hr equals 15 Attention : this only translates into an angular distance on the equator, not at higher declinations. Summarizing:
Images Of Mathematicians On Postage Stamps hipparchus of rhodes. Issued by Greece hipparchus1.jpg. HRONEC, Juraj. Issued byCzechoslovakia on March 10, 1981, part of an eightstamp series Famous http://jeff560.tripod.com/
Extractions: Images of Mathematicians on Postage Stamps RECENT CHANGES: On Aug. 23, graph17.jpg was added. On Aug. 22, goldensection3.jpg was added. Thanks to Magnus Waller for these images. On Aug. 14, abel10.jpg, abacus9.jpg, abacus10.jpg, graph16.jpg, computing1.jpg, and binary1.jpg were added. Thanks to Heinz Klaus Strick for these images. On Aug. 6, pascal4.jpg was added. On July 18, newton52.jpg, abacus8.jpg, hieroglyphics2.jpg, graph15.jpg, and fractal3.jpg were added. Thanks to Magnus Waller for these images. ABEL, Niels Henrik. Issued by Norway on April 6, 1929, upon the death centenary abel1.jpg abel2.jpg abel3.jpg abel4.jpg ; issued by Norway on June 5, 2002, on the two-hundredth anniversary of his birth abel5.jpg abel6.jpg abel8.jpg abel9.jpg ; a coin issued by Norway in 2002 on the 200th anniversary of his birth abel7.jpg ; issued by Norway in 1983, showing the Abel monument by Gustav Vigeland abel10.jpg AIRY, George B. Issued by Nicaragua in 1994 as part of a series depicting astronomers airy.jpg ; issued by Great Britain in 1984 airy2.jpg
OML: Neptune's Realm: Ocean Divided hipparchus of rhodes (c. 167127 BC), one of the greatest of Greek astronomers,had marked off the earth s surface at the equator into 360 partsthe http://www.usm.maine.edu/maps/exhibit8/nrlong.html
Extractions: Charting Neptune's Realm An Ocean Divided As voyaging increased into the uncharted regions of the open ocean, mariners brought back their findings to be retained in written records and represented on maps. To create accurate maps cartographers needed more than recounted tales and estimated distances. It became apparent that a grid system dividing the earth into coordinates of latitude and longitude was necessary. Thus, a grid was constructed whereupon any point on the earth's surface could be located. London: Sayer and Bennet, 1777 In his "New General Chart of the Atlantic or Western Ocean and Adjacent Seas," de Fleurieu placed great emphasis on geographic accuracy as determined by astronomical observations for latitude and longitude. On this English edition of one of his charts, two prime meridiansthe starting line of zero degrees longitudeare indicated by longitude scales at the top of the chart: one, located at the Greenwich Observatory in England; the other, positioned in Paris. A third scale at the bottom of the chart shows Time in hours and minutes, in effect another way of indicating longitude. Even latitude, with its fixed reference points of the equator and poles, is marked off in two different scales. Latitude on the left-hand margin of the chart is measured in degrees, while latitude on the right-hand margin is expressed in marine leagues.
BSHM: Abstracts -- H of hipparchus of rhodes , Bulletin CSHPM 26 (2000), 45, 11 The chord table thatHipparchus constructed and used no longer exists either in its original or http://www.dcs.warwick.ac.uk/bshm/abstracts/H.html
Extractions: The British Society for the History of Mathematics HOME About BSHM BSHM Council Join BSHM ... Search A B C D ... Z These listings contain all abstracts that have appeared in BSHM Newsletters up to Newsletter 46. BSHM Abstracts - H Habib, S Irfan and Dhruv Raina, The introduction of scientific rationality into India: a study of Master RamchundraUrdu journalist, mathematician and educationalist, Annals of science The contradictions shown in Ramchundras projects were the products of contradictions in the political and ideological thinking of the period. He gave a critique of prevalent systems, and also a call for social transformation from a stance close to that of Comtean positivists, which can be located within the context of C19 colonial politics. Hackmann, Willem, Mathematical instruments, in John Fauvel, Raymond Flood and Robin Wilson (eds), Oxford figures: 800 years of the mathematical sciences , Oxford University Press 1999, 62-75 A striking aspect of the development of practical mathematics from C16 to C18 is the importance of the craft base, the ease with which skills in paper engraving were translated into those of instrument making, and the cohesion of the circle of scholars, practitioners and instrument makers. Hadley, John and David Singmaster, Problems to sharpen the young
