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1. A representation of a sphere or part of a sphere on a plane surface.
2. Astronomy A polar projection of half or more of the celestial sphere on a chart equipped with an adjustable overlay to show the stars visible at a particular time and place.

pla′ni·spher′ic (-sfîr′ĭk, -sfĕr′-), pla′ni·spher′i·cal (-ĭ-kəl) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
It pushes back our knowledge about these important instruments by at least 30 years and it appears to be a transitional form from a planispheric astrolabe to one used at sea.
A Latinized version of his planispheric map was included in his Coelum Australe Stelliferum, published posthumously.
Modern day planispheric astrolabe designed for the latitude of Varese (Italy), drawn by the Shadows Pro shareware.
Kim, director and CEO, Aga Khan Museum, Toronto Image Credit: A planispheric astrolabe from Spain Image Credit: A carved marble capital from Spain Image Credit: Incised mother-of-pearl shell with inscriptions, from India Image Credit: A fritware, underglazed dish from Iran Image Credit: A porcelain ablution basin from Jingdezhen, China Image Credit: Carved ivory horn with silver mount from southern Italy Image Credit:
The emergence of the astrolabe as a single instrument began with the bringing together of two forerunners in Greece in the second century BC: the dioptra--an instrument for sighting the altitudes of celestial bodies--and planispheric projections which could be used to represent the celestial sphere on a flat surface.
Scheme Lens Sigma 8mm Sigma 4.5mm F2.8 Nikkor 10mm F5.6 f/3.5 (Fan and OP others 2009; Inanici 2009; 2010; Stumpfel and others 2004;Van Den Wymelenberg and others 2010) Nikon FC-E8 (Jacobs and Wilson 2007) Nikon FC-E9 (Inanici 2006) Nikkor 8mm f/2.8 Projection Stereographic (also type called planispheric) Projection r = formula 2*f*tan([theta]/2) Scheme Lens Samyang 8mm
Almost every image in this sumptuously printed monograph includes a scientific instrument of some kind, including magnifying lenses, a military compass, sundials, prisms, and a planispheric astrolabe from c.