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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



an auxiliary point in the Ptolemaic system (the point E in the figure), introduced by Ptolemy to match observed planetary motions with motions previously calculated with deferents and epicycles.

Figure 1

Describing the motion of the planets with circles and constant angular velocities, Ptolemy placed the earth (T) outside the center of the deferent (C). He assumed that the center of the epicycle (O) of a planet moved nonuniformly along the deferent, but in such a manner that the motion seemed uniform to an observer located at the equant, which was symmetric to the position of the earth relative to the center of the deferent.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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The presence of cavity spar and equant blocky cement suggest role of meteoric water during burial (Bjorlykke, 2014).
This paper offers a close reading of Ptolemy's philosophical defense of the equant in Almagest 9.2.
Microsparite and sparite calcite crystals are mostly equant to elongated rhombohedrons or scalenohedrons, but also a few prismatic crystals were observed.
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Pyroxene: The pyroxene is mainly represented by both, ortho- and clinohypersthene, occurring as small euhedral to subhedral prismatic crystals and square or equant basal sections.
Veraz's strong installed base of existing customers in Russia includes Equant, Vimpelcom, MTT, Rostelecom and Golden Telecom.
Other companies already on Key Business Park include outsourcing and distribution company Bunzl, architectural ironmongers suppliers Eisenwareswann and data communications specialist Equant. Bigwood director Les Balla said: "This cluster of high net worth companies underlines that Key Business Park is an attractive proposition and there are still many top companies waiting to relocate to Birmingham."
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Monocrystalline quartz: equant to slightly elongate, straight extinction.