HIPPARCHUS

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References





Edition and translation: Karl Manitius: In Arati et Eudoxi Phaenomena, Leipzig, 1894.

J. Chapront, M. Chapront Touze, G. Francou (2002): "A new determination of lunar orbital parameters, precession constant, and tidal acceleration from LLR measurements". Astronomy and Astrophysics 387, 700-709.

Duke, Dennis W. (2002). Associations between the ancient star catalogs. Archive for the History of Exact Sciences 56(5):435-450.

A. Jones: "Hipparchus." In Encyclopedia of Astronomy and Astrophysics. Nature Publishing Group, 2001.
 
Patrick Moore (1994): Atlas of the Universe, Octopus Publishing Group LTD (Slovene translation and completion by Tomaž Zwitter and Savina Zwitter (1999): Atlas vesolja), 225.
 
Newton, R.R. (1977). The Crime of Claudius Ptolemy. Baltimore: Johns Hopkins University Press.

Rawlins, Dennis (1982). An Investigation of the Ancient Star Catalog. Proceedings of the Astronomical Society of the Pacific 94, 359-373. Has been updated several times: DIO, volume 8, number 1 (1998), page 2, note 3, and DIO, volume 10 (2000), page 79, note 177.

J.M.Steele, F.R.Stephenson, L.V.Morrison (1997): "The accuracy of eclipse times measured by the Babylonians". Journal for the History of Astronomy xxviii, 337..345

F.R. Stephenson, L.J.Fatoohi (1993): "Lunar Eclipse Times Recorded in Babylonian History". Journal for the History of Astronomy xxiv, 255..267

N.M. Swerdlow (1969): "Hipparchus on the distance of the sun." Centaurus 14, 287-305.

G.J. Toomer (1967): "The Size of the Lunar Epicycle According to Hipparchus." Centaurus 12, 145-150.
 
G.J. Toomer (1973): "The Chord Table of Hipparchus and the Early History of Greek Trigonometry." Centaurus 18, 6-28.

G.J. Toomer (1974): "Hipparchus on the Distances of the Sun and Moon." Archives for the History of the Exact Sciences 14, 126-142.

G.J. Toomer (1978): "Hipparchus." In Dictionary of Scientific Biography 15: 207-224.

G.J. Toomer (1980): "Hipparchus' Empirical Basis for his Lunar Mean Motions," Centaurus 24, 97-109.

G.J. Toomer (1988): "Hipparchus and Babylonian Astronomy." In A Scientific Humanist: Studies in Memory of Abraham Sachs, ed. Erle Leichty, Maria deJ. Ellis, and Pamel Gerardi. Philadelphia: Occasional Publications of the Samuel Noah Kramer Fund, 9.


http://www.crystalinks.com/greekastronomy.html

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                                                             External links





General



O'Connor, John J; Edmund F. Robertson "Hipparchus". MacTutor History of Mathematics archive.   

Biographical page at the University of Cambridge

University of Cambridge's Page about Hipparchus' sole surviving work

Biographical page at the University of Oregon

Biography of Hipparchus on Fermat's Last Theorem Blog

Pastore, Giovanni, ANTIKYTHERA E I REGOLI CALCOLATORI, Rome, 2006, privately published

The Antikythera Calculator (Italian and English versions)





Precession



David Ulansey about Hipparchus's understanding of the precession






Celestial bodies



M44 Praesepe at SEDS (University of Arizona): http://www.seds.org/messier/m/m044.html






Star catalog



A brief view by Carmen Rush on Hipparchus' stellar catalog

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v • d • eGreek mathematics





Mathematicians Anaxagoras · Anthemius · Archytas · Aristaeus the Elder · Aristarchus · Apollonius · Archimedes · Autolycus · Boethius · Bryson · Callippus · Chrysippus · Cleomedes · Conon · Ctesibius · Democritus · Dicaearchus · Diocles · Diophantus · Dinostratus · Dionysodorus · Domninus · Eratosthenes · Eudemus · Euclid · Eudoxus · Eutocius · Geminus · Heron · Hipparchus · Hippasus · Hippias · Hippocrates · Hypatia · Hypsicles · Marinus · Menaechmus · Menelaus · Nicomachus · Nicomedes · Nicoteles · Oenopides · Pappus · Perseus · Philolaus · Philon · Porphyry · Posidonius · Proclus · Ptolemy · Pythagoras · Pytheas · Serenus  · Simplicius · Sosigenes · Sporus · Thales · Theaetetus · Theano · Theodorus · Theodosius · Theon of Alexandria · Theon of Smyrna · Thymaridas · Xenocrates · Zeno of Elea · Zeno of Sidon · Zenodorus





Treatises


Almagest · Archimedes Palimpsest · Arithmetica · Conics · Elements · On the Sizes and Distances

(Aristarchus) · On Sizes and Distances (Hipparchus)

Centers Academy of Athens · Library of Alexandria · Cyrene

Influences Babylonian mathematics  · Egyptian mathematics

Influenced Islamic mathematics  · Indian mathematics



Retrieved from "http://en.wikipedia.org/wiki/Hipparchus"





Categories:


Ancient Greek astronomers | Ancient Greek geographers | Ancient Greek mathematicians | Ancient Greek astrologers | 190 BC births | 120 BC deaths | Scientific instrument makers

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                                                        Star catalogue





A star catalogue, or star catalog, is an astronomical catalog that lists stars.

In astronomy, many stars are referred to simply by catalogue numbers.

There are a great many different star catalogues which have been produced for different purposes over the years, and this article covers only some of the more frequently quoted ones.

Most of the recent catalogues are available in electronic format and can be freely downloaded from NASA's Astronomical Data Center and other places

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Historical catalogues





The world's first star catalogue was compiled by Shi Shen and Gan De, both Chinese astronomers in the 4th century BC of the Warring States Period. Shi Shen wrote the Shi Shen astronomy (石申天文, Shi Shen tienwen), while Gan De wrote the Astronomic star observation (天文星占, Tianwen xingzhan).

In approximately the 3rd century BC, Timocharis of Alexandria and Aristillus created the first star catalogue in the Western world.

Over 150 years later, Hipparchus would compare his own star catalogue to Timocharis' and discover that the longitude of the stars had changed over time, which led him to determine the first value of the precession of the equinoxes.

In the 2nd century, Ptolemy published a star catalogue as part of his Almagest, which listed 1,022 stars visible from Alexandria. It was the standard star catalogue in the Western and Arab worlds for over a thousand years. Ptolemy's catalogue was based almost entirely on an earlier one by Hipparchus from the 2nd century BC (Newton 1977; Rawlins 1982).







Bayer and Flamsteed catalogues





Two systems introduced in historical catalogues remain in use to the present day.

The first system comes from Bayer's Uranometria and is for bright stars. These are given a Greek letter followed by the genitive case of the constellation in which they are located; examples are Alpha Centauri or Gamma Cygni. See Bayer designation for more information. The major problem with Bayer's naming system was the number of letters in the Greek alphabet. It was easy to run out of letters before running out of stars needing names, particularly for large constellations such as Argo Navis. Bayer extended his lists up to 67 stars by using lower-case Roman letters ("a" through "z") then upper-case ones ("A" through "Q").

Few of those designations have survived. It is worth mentioning, however, as it served as the starting point for variable star designations, which start with "R" through "Z", then "RR", "RS", "RT"..."RZ", "SS", "ST"..."ZZ" and beyond.

The second system comes from John Flamsteed's Historia coelestis Britannica. It kept the genitive-of-the-constellation rule for the back end of his catalog names, but used numbers instead of the Greek alphabet for the front half. Examples include 61 Cygni and 47 Ursae Majoris; see Flamsteed designation for more information.

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References





Newton, Robert R. (1977). The Crime of Claudius Ptolemy. Baltimore: Johns Hopkins University Press.
Rawlins, Dennis (1982). An investigation of the ancient star catalog. Pub. Astron. Soc. Pacific 94, 359.



Full-sky catalogues

Bayer and Flamsteed covered only a few thousand stars between them. In theory, full-sky catalogues try to list every star in the sky. There are, however, literally hundreds of millions, even billions of stars resolvable by telescopes, so this is an impossible goal; these kind of catalogs generally try to get every star brighter than a given magnitude.



HD/HDE

Main article: Henry Draper Catalogue

The Henry Draper Catalogue was published in the period 1918–1924. It covers the whole sky down to about ninth or tenth magnitude, and is notable as the first large-scale attempt to catalogue spectral types of stars. The catalogue was compiled by Annie Jump Cannon and her co-workers at Harvard College Observatory under the supervision of Edward Pickering, and was named in honour of Henry Draper, whose widow donated the money required to finance it.

HD numbers are widely used today for stars which have no Bayer or Flamsteed designation. Stars numbered 1–225300 are from the original catalogue and are numbered in order of right ascension for the 1900.0 epoch. Stars in the range 225301–359083 are from the 1949 extension of the catalogue. The notation HDE can be used for stars in this extension, but they are usually denoted HD as the numbering ensures that there can be no ambiguity.



SAO

Main article: Smithsonian Astrophysical Observatory Star Catalog

The Smithsonian Astrophysical Observatory catalogue was compiled from various previous astrometric catalogues, and contains only the stars to about ninth magnitude for which accurate proper motions were known. There is considerable overlap with the Henry Draper catalogue, but any star lacking motion data is omitted. The epoch for the position measurements in the latest edition is J2000.0. The SAO catalogue contains this major piece of information not in Draper, the proper motion of the stars, so it is often used when that fact is of importance. The cross-references with the Draper and Durchmusterung catalogue numbers in the latest edition are also useful.

Names in the SAO catalogue start with the letters SAO, followed by a number. The numbers are assigned following 18 ten-degree bands in the sky, with stars sorted by right ascension within each band.



BD/CD/CPD

Main article: Durchmusterung

The Bonner Durchmusterung (German: Bonn sampling) and follow-ups were the most complete of the pre-photographic star catalogues.

The Bonner Durchmusterung itself was published by Friedrich Wilhelm Argelander, Adalbert Krüger, and Eduard Schönfeld between 1852 and 1859. It covered 320,000 stars in epoch 1855.0.

As it covered only the northern sky and some of the south (being compiled from the Bonn observatory), this was then supplemented by the Südliche Durchmusterung (SD), which covers stars between declinations -1 and -23 degrees (1886, 120,000 stars). It was further supplemented by the Cordoba Durchmusterung (580,000 stars), which began to be compiled at Córdoba, Argentina in 1892 under the initiative of John M. Thome and covers declinations -22 to -90. Lastly, the Cape Photographic Durchmusterung (450,000 stars, 1896), compiled at the Cape, South Africa, covers declinations -18 to -90.

Astronomers preferentially use the HD designation of a star, as that catalogue also gives spectroscopic information, but as the Durchmusterungs cover more stars they occasionally fall back on the older designations when dealing with one not found in Draper. Unfortunately, a lot of catalogues cross-reference the Durchmusterungs without specifying which one is used in the zones of overlap, so some confusion often remains.

Star names from these catalogues include the initials of which of the four catalogues they are from (though the Southern follows the example of the Bonner and uses BD; CPD is often shortened to CP), followed by the angle of declination of the star (rounded towards zero, and thus ranging from +00 to +89 and -00 to -89), followed by an arbitrary number as there are always thousands of stars at each angle. Examples include BD+50°1725 or CD-45°13677.



AC

The Catalogue astrographique (Astrographic Catalogue) was part of the international Carte du Ciel programme designed to photograph and measure the positions of all stars brighter than magnitude 11.0. In total, over 4.6 million stars were observed, many as faint as 13th magnitude. This project was started in the late 1800s. The observations were made between 1891 and 1950. To observe the entire celestial sphere without burdening only a handful of institutions, the sky was divided among 20 observatories, by declination zones. Each observatory exposed and measured the plates of its zone, using a standardized telescope (a "normal astrograph") so each plate photographed had a similar scale of approximately 60 arcsecs/mm. The U.S. Naval Observatory took over custody of the catalogue, now in its 2000.2 edition.



USNO-B1.0

USNO-B1.0 is an all-sky catalog created by researchers at the U.S. Naval Observatory that presents positions, proper motions, magnitudes in various optical passbands, and star/galaxy estimators for 1,042,618,261 objects derived from 3,643,201,733 separate observations. The data were obtained from scans of 7,435 Schmidt plates taken for the various sky surveys during the last 50 years. USNO-B1.0 is believed to provide all-sky coverage, completeness down to V = 21, 0.2 arcsecond astrometric accuracy at J2000.0, 0.3 magnitude photometric accuracy in up to five colors, and 85% accuracy for distinguishing stars from non-stellar objects.

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Specialized catalogues





Specialized catalogs make no effort to list all the stars in the sky, working instead to highlight a particular type of star, such as variables or nearby stars.



ADS

Aitken's double star catalogue

New general catalogue of double stars within 120 deg of the North Pole (1932, R. G. Aitken).
This lists 17,180 double stars north of declination -30 degrees.



BS, BSC, HR

Main article: Bright Star Catalogue

First published in 1930 as the Yale Catalog of Bright Stars, this catalog contained information on all stars brighter than visual magnitude 6.5 in the Harvard Revised Photometry Catalogue. The list was revised in 1983 with the publication of a supplement that listed additional stars down to magnitude 7.1. The catalog detailed each star's coordinates, proper motions, photometric data, spectral types, and other useful information.

The last printed version of the Bright Star Catalogue was the 4th revised edition, released in 1982. The 5th edition is in electronic form and is available online.



GJ, Gliese, Gl

The Gliese (later Gliese-Jahreiß) catalogue attempts to list all stars within 20 parsecs of Earth ordered by right ascension (see the List of nearest stars). Later editions expanded the coverage to 25 parsecs. Numbers in the range 1.0–965.0 (Gl numbers) are from the second edition, which was



Catalogue of Nearby Stars (1969, W. Gliese).
 
The integers up to 915 represent stars which were in the first edition. Numbers with a decimal point were used to insert new stars for the second edition without destroying the desired order (by right ascension). This catalogue is referred to as CNS2, although this name is never used in catalogue numbers.



Numbers in the range 9001–9850 are from the supplement

Extension of the Gliese catalogue (1970, R. Woolley, E. A. Epps, M. J. Penston and S. B. Po****).
Numbers in the ranges 1000–1294 and 2001–2159 (GJ numbers) are from the supplement



Nearby Star Data Published 1969–1978 (1979, W. Gliese and H. Jahreiß).

The range 1000–1294 represents nearby stars, while 2001–2159 represents suspected nearby stars. In the literature, the GJ numbers are sometimes retroactively extended to the Gl numbers (since there is no overlap). For example, Gliese 436 can be interchangeably referred to as either Gl 436 or GJ 436.



Numbers in the range 3001–4388 are from

Preliminary Version of the Third Catalogue of Nearby Stars (1991, W. Gliese and H. Jahreiß).
Although this version of the catalogue was termed "preliminary", it is still the current one as of March 2006, and is referred to as CNS3. It lists a total of 3,803 stars. Most of these stars already had GJ numbers, but there were also 1,388 which were not numbered (plus the Sun, which needs no number). The need to give these 1,388 some name has resulted in them being numbered 3001–4388 (NN numbers, for "no name"), and data files of this catalogue now usually include these numbers. An example of a star which is often referred to by one of these unofficial GJ numbers is GJ 3021.



GCTP

The General Catalogue of Trigonometric Parallaxes, first published in 1952 and later superseded by the New GCTP (now in its fourth edition), covers nearly 9,000 stars. Unlike the Gliese, it does not cut off at a given distance from the Sun; rather it attempts to catalogue all known measured parallaxes. It gives the co-ordinates in 1900 epoch, the secular variation, the proper motion, the weighted average absolute parallax and its standard error, the number of parallax observations, quality of interagreement of the different values, the visual magnitude and various cross-identifications with other catalogues. Auxiliary information, including UBV photometry, MK spectral types, data on the variability and binary nature of the stars, orbits when available, and miscellaneous information to aid in determining the reliability of the data are also listed.

William F. van Altena, John Truen-liang Lee and Ellen Dorrit Hoffleit, Yale University Observatory, 1995.



HIP

The Hipparcos catalogue was compiled from the data gathered by the European Space Agency's astrometric satellite Hipparcos, which was operational from 1989 to 1993. The catalogue was published in June 1997 and contains 118,218 stars. It is particularly notable for its parallax measurements, which are considerably more accurate than those produced by ground-based observations.

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Proper motion catalogues





A common way of detecting nearby stars is to look for relatively high proper motions. Several catalogues exist, of which we'll mention a few. The Ross and Wolf catalogues pioneered the domain:



Ross, Frank Elmore, New Proper Motion Stars, twelve successive lists, The Astronomical Journal, Vol. 36 to 48, 1925-1939

Wolf, Max, "Katalog von 1053 stärker bewegten Fixsternen", Veröff. d. Badischen Sternwarte zu Heidelberg (Königstuhl), Bd. 7, No. 10, 1919; and numerous lists in Astron. Nachr. 209 to 236, 1919-1929


Willem Jacob Luyten later produced a series of catalogues:

L - Luyten, Proper motion stars and White dwarfs

Luyten, W. J., Proper Motion Survey with the forty-eight inch Schmidt Telescope, University of Minnesota, 1941 (General Catalogue of the Bruce Proper-Motion Survey)
LFT - Luyten Five-Tenths catalogue

Luyten, W. J., A Catalog of 1849 Stars with Proper Motion exceeding 0.5" annually, Lund Press, Minneapolis (Mn), 1955
LHS - Luyten Half-Second catalogue

Luyten, W. J., Catalogue of stars with proper motions exceeding 0"5 annually, University of Minnesota, 1979 ([3])
LTT - Luyten Two-Tenths catalogue

Luyten, W. J., Catalogue of stars with proper motions exceeding 0"2 annually, Univ. of Minnesota, 1980 ([4])
LPM - Luyten Proper-Motion catalogue

Luyten, W. J., Proper Motion Survey with the 48 inch Schmidt Telescope, University of Minnesota, 1963-1981
Later, Henry Lee Giclas took over, again with a series of catalogues:

Giclas, H. L., et al., Lowell Proper Motion Survey, Lowell Observatory Bulletins, 1971-1979 ([5])



See also

List of Star catalogues






 Notes



^ Gan De. Crónicas del Bambú. (365 aC).

^ [Peng, Yoke Ho (2000). Li, Qi and Shu: An Introduction to Science and Civilization in China. Courier Dover Publications. ISBN 0486414450]





External links



NASA Astronomy Data Center

Centre de Données astronomiques de Strasbourg

Sloan Digital Sky Survey

IAU FAQ on "Naming Stars"

Name a Star? The Truth about Buying Your Place in Heaven

Astronomical Catalog Designations: Standardized List for Online Databases
 
Hartmut Frommert's list of star catalogues

Gaia astrometric satellite


 
Retrieved from "http://en.wikipedia.org/wiki/Star_catalogue"

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                                                    A S T R O L A B E





This article is about the astronomical instrument. For French exploration ships, see French ship Astrolabe. For
the bay in Papua New Guinea named after this ship, see Astrolabe Bay.

For the nautical instrument, see Mariner's astrolabe.
 

The astrolabe is a historical astronomical instrument used by classical astronomers, navigators, and astrologers.

Its many uses included locating and predicting the positions of the Sun, Moon, planets
and stars; determining local time given local longitude and vice-versa; surveying; and triangulation.

In the Islamic world, they are and were used primarily for astronomical studies, though astrology was often involved there as well. Astrologers of the European nations used astrolabes to construct horoscopes.

There is often confusion between the astrolabe and the mariner's astrolabe. While the astrolabe could
be useful for determining latitude on land, it was an awkward instrument for use on the heaving deck
of a ship or in wind. The mariner's astrolabe was developed to address these issues.

The astrolabe was invented in the Hellenistic world in either the first or second centuries BCE and is often attributed to Hipparchus. A marriage of the planisphere and dioptra, the astrolabe was effectively an analog calculator capable of working out several different kinds of problems in spherical astronomy.

Theon of Alexandria wrote a detailed treatise on the astrolabe, and Lewis (2001) argues that Ptolemy used
an astrolabe to make the astronomical observations recorded in the Tetrabiblos.


http://en.wikipedia.org/wiki/Astrolabe

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ARMILLARY SPHERE

An armillary sphere (variations are known as spherical astrolabe, armilla, or armil)
is a model of the celestial sphere.






The earliest known armillary sphere was invented by the ancient Greek Eratosthenes in 255 BC.

The Chinese during the 1st century BC (Western Han Dynasty) also invented the armillary sphere, while
the 2nd century Chinese astronomer Zhang Heng is credited as the world's first to apply motive power
(using hydraulics) in rotating his armillary sphere.

The name of this device comes ultimately from the Latin armilla (circle, bracelet), since it has a skeleton
made of graduated metal circles linking the poles and representing the equator, the ecliptic, meridians and
parallels (while the Chinese dubbed theirs as the hun yi, or celestial-sphere instrument).

Usually a ball representing the Earth or, later, the Sun is placed in its center. It is used to demonstrate
the motion of the stars around the Earth. Before the advent of the European telescope in the 17th century,
the armillary sphere was the prime instrument of all astronomers in determining celestial positions.

In its simplest form, consisting of a ring fixed in the plane of the equator, the armilla is one of the most
ancient of astronomical instruments. Slightly developed, it was crossed by another ring fixed in the
plane of the meridian. The first was an equinoctial, the second a solstitial armilla. Shadows were used as
indices of the sun's positions, in combinations with angular divisions. When several rings or circles were
combined representing the great circles of the heavens, the instrument became an armillary sphere.

Eratosthenes most probably used a solstitial armilla for measuring the obliquity of the ecliptic. Hipparchus probably used an armillary sphere of four rings. Ptolemy describes his instrument in the Syntaxis (book v. chap. i). It consisted of a graduated circle inside which another could slide, carrying to small tubes diametrically opposite, the instrument being kept vertical by a plumb-line.

Armillary spheres were developed by the Greeks and were used as teaching tools already in the 3rd century B.C.. In larger and more precise forms they were also used as observational instruments.


http://en.wikipedia.org/wiki/Armillary_sphere

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THE GNOMON

The gnomon is the triangular blade in this sundial.






The gnomon is the part of a sundial that casts the shadow. Gnomon is an ancient Greek word meaning "indicator", "one who discerns," or "that which reveals."

 
In the northern hemisphere, the shadow-casting edge is normally oriented so that it points north and is parallel to the rotation axis of the Earth. That is, it is inclined to the horizontal at an angle that equals the latitude of the sundial's location. On some sundials, the gnomon is vertical. These were usually used in former times for observing the altitude of the sun, especially when on the meridian.

The style is the part of the gnomon that casts the shadow. This can change as the sun moves. For example, the upper west edge of the gnomon might be the style in the morning and the upper east edge might be the style in the afternoon.

The art of constructing a gnomon sundial is sometimes termed gnomonics. One so skilled would be referred to as a gnomonist.

Gnomon may also imply the design paradigm relationship between an indicator and a dial or other reference, as with a speedometer and needle. In this case, the needle functions as a gnomon against the incremented speedometer background.

Gnomon is also a mathematical term that describes the part of a parallelogram that remains when a similar parallelogram is removed from one of its corners.

Also, gnomon is the name given to an aesthetic process utilised by James Joyce in his set of short stories Dubliners, whereby the whole of the character is revealed by a single part.

Anaximander (610–546 BC) is credited with introducing this Babylonian instrument to the Greeks. The Chinese also used the gnomon, mentioned in the 2nd century Nine Chapters on the Mathematical Art as being used much earlier by the Duke of Zhou (11th century BC).


http://en.wikipedia.org/wiki/Gnomon

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Scaphion





From Wikipedia, the free encyclopedia

The scaphion was a portable gnomon, developed by hellenistic astronomers. They put a gnomon in a metallic hemisphere, which was divided inside in concentric circles. They could use it for determination of geographical coordinates from measured solar altitudes. Using this measuring instrument Eratosthenes of Cyrene (ca. 220 BC) had measured the length of Earth's meridian, and after that they used this instrument to survey smaller regions as well.




FOR MORE ON THE GNOMON/SUNDIAL:


http://atlantisonline.smfforfree2.com/index.php/topic,5556.0.html