analemman.
/ˌanəˈlɛmə/, U.S. /ˌænəˈlɛmə/ Chiefly Astronomy.
1. An orthographical projection of the celestial sphere on to the plane of the meridian, the observer being supposed to be at an infinite distance at the east or west point of the horizon. In later use chiefly historical (frequently attributive).
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the world > the universe > cosmology > science of observation > astronomical instruments > used in dialling > [noun] > orthographical projection
analemma1652
1652 R. Austin Let. in S. P. Rigaud & S. J. Rigaud Corr. Sci. Men 17th Cent. (1841) (modernized text) I. 74 The triangles, either in your Analemma or perspective, which serve for the last propositions in your astronomical operations.
1669 Philos. Trans. 1668 (Royal Soc.) 3 872 The Orthographick Projection, by Perpendiculars falling from the respective Points of the Circles of the Spheare, on the Projecting Plain: Such a Projection, if the Plain be the Meridian, Ptolemy called the Analemma.
1693 E. Halley in Philos. Trans. (Royal Soc.) 17 881 Fig. 10..is the Analemma projected on the Plain of the Meridian.
1715 H. Wilson Navigation new Modell’d viii. 225 How to make an Orthographick Projection of the Sphere, commonly called the Analemma.
?1770 B. Martin Princ. Perspective ix. 47 This Projection is of little Use in Geography, but of very great Use in Astronomical Sciences, and is known by the Names of Analemma, and Orthographical Projection of the Sphere.
1917 Amer. Math. Monthly 24 163 Johannes de Rojas..projected the sphere orthographically on the plane of the solstitial colure, the result being the ‘Analemma’.
1972 Proc. Amer. Philos. Soc. 116 249/2 That Hipparchus had no spherical trigonometry in the proper sense is certain... This does not exclude, however, the possibility of solving certain problems of spherical astronomy by means of the so-called ‘Analemma’ methods... Analemma methods play a vital role also in Indian astronomy.
1997 J. V. Field Invention of Infinity ii. 28 Vitruvius' text On architecture, where superposition of lines from perpendicular planes is used in the famous ‘analemma’ construction for the lines on sundials.
2. An instrument or part constructed on the basis of the analemma projection.
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the world > the universe > cosmology > science of observation > astronomical instruments > [noun] > astrolabe > planisphere
planispherea1393
analem1635
analemma1667
star-wheel1982
1667 Philos. Trans. (Royal Soc.) 2 436 A good Globe or Planisphere..that is, the Analemma, contrived into a form of Instrument for the use of the publick.
1685 J. Twisden (title) Use of the great planisphere called the analemma in the resolution of some useful problems of astronomy.
1796 C. Hutton Math. & Philos. Dict. (new ed.) I. 106 The oldest treatise we have on the analemma, was written by Ptolemy.
1829 Encycl. Americana I. 430/1 Astrolabe (planisphere, analemma).
1930 Jrnl. Biblical Lit. 49 317 The fullest discussion of these solar instruments is given by Vitruvius, De Architectura, ix, cc. 7, 8 on the Analemma and on Sundials and Waterclocks.
1935 Classical Philol. 30 338 The application of the analemma in Rome required adjustment as compared with the latitude of Syracuse.
1954 Sci. Monthly May 277/1 (caption) Side view of the Briggs' sundial, showing the three gnomons and the curved analemma plate.
1974 Jrnl. Warburg & Courtauld Inst. 37 257/2 Testa not only observed shadows, but also carefully studied the section in Barbaro's commentary wherein is discussed the method of constructing an Analemma, a conical solid used for telling the time according to shadows.
3. A scale drawn on a terrestrial globe showing the changing position of the true sun over the course of a year; a similar item on a sundial.When the sun's declination is shown on the y-axis, and the equation of time (the difference between sundial time and clock time) on the x-axis, the resulting curve is a distorted figure 8. Other conventions result in other shapes. On a globe an analemma is traditionally placed in the Pacific Ocean where it least interferes with geographical features.
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the world > the universe > cosmology > science of observation > astronomical instruments > representational device > [noun] > map of heavens > sun
analemma1769
1769 B. Donne Epitome Nat. & Exper. Philos. vi. 55 On some late Globes, a Piece of Paper called an Analemma, is pasted on, shewing by Inspection the Declination answering to any Day of the Month.
1800 J. Vint Conc. Syst. Mod. Geogr. I. 31 A kind of calendar on a narrow slip of paper, and called an analemma, containing the months and days; and also the sun's declination for each day. This slip..is on some globes pasted across the equator at the vernal equinox.
1826 T. Keith New Treat. Use of Globes (ed. 2) 110 Bring the analemma to the brass meridian, and the degree above this day will be the sun's declination.
1877 G. F. Chambers Handbk. Descr. Astron. (ed. 3) 911 Analemma, a scale painted on globes, and having reference to the motion of the Sun.
1964 D. Greenhood Mapping ii. 38 In the days before radio, the analemma..was useful for correcting clocks. It is still useful in reading sun dials.
1970 Jrnl. Brit. Astron. Assoc. 80 244 A very interesting description of the ingenious methods employed to allow for the equation of time on equatorial dials by using a gnomon in the shape of an analemma.
1999 Clocks Dec. 31/2 In appearance, the ‘Roger Cowell’ sundial is very simple. It takes the form of a gilded analemma , the figure-of-eight that allows for the equation of time correction, superimposed on a plain vertical noon-line.
4. The curve traced in the sky at a given place by the position of the sun at the same mean solar time on successive days of a year.For terrestrial locations, the analemma is an asymmetric figure of eight, and is typically calculated for twelve o'clock standard time.
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the world > relative properties > number > geometry > curve > [noun] > other
quadratrix1656
section1665
family1705
semiparabola1728
tractrix1728
witcha1760
tractory1820
sinusoid1823
tractatrix1828
indicatrix1841
hodograph1847
tetrazomal1867
space curve1875
horograph1879
hypercycle1889
Peano curve1900
multiple arc1967
unknot1971
fractal1975
analemma1978
1978 Jrnl. Brit. Astron. Assoc. 88 476 Plotting the shadow's position at the same Mean Time each day produces a projection of the analemma on the dial, the lines of projection from the Sun to the dial passing through the point which casts the shadow.
1990 D. H. Menzel & J. M. Pasachoff Field Guide Stars & Planets vii. 244 A multiple exposure of the sun's position over a year, making an analemma.
1993 Math. Gaz. 77 94 The position of the sun at (mean solar) noon traces out a figure of eight pattern in the sky known as the analemma.
2004 New Yorker 5 Jan. 28/1 They notice that the analemma on Mars is not figure-eight-shaped.
This entry has been updated (OED Third Edition, November 2010; most recently modified version published online December 2021).
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