Published June 1987
by New York Academy of Sciences .
Written in English
| The Physical Object | |
|---|---|
| Format | Paperback |
| ID Numbers | |
| Open Library | OL9510083M |
| ISBN 10 | 0897663969 |
| ISBN 10 | 9780897663960 |
From deferent to equant. New York, N.Y.: New York Academy of Sciences, (OCoLC) Named Person: E S Kennedy; E S Kennedy: Material Type: Internet resource: Document Type: Book, Internet Resource: All Authors / Contributors: E S Kennedy; David A King; George Saliba. Book Review: From deferent to equant: a volume of studies in the history of science in the ancient and medieval near east in honor of E. S. Kennedy. / New York Academy of Sciences, North, J. From deferent to equant: A Volume of Studies in the History of Science in the Ancient and Medieval Near East in Honor of E. S. Kennedy Book February with Reads How we measure 'reads'. The centre of the deferent is midway between the equant and Earth. Encyclopædia Britannica, Inc. Learn about this topic in these articles: definition by Ptolemy. In Ptolemaic system point that he called the equant. The centre of the deferent was located midway between the equant and the Earth, as can be seen in the figure.
From Deferent to Equant: A Volume of Studies on the History of Science of the Ancient and Medieval Near East in Honor of ES Kennedy Pages: ix-xxix, June From Deferent to Equant: A Volume of Studies in the History of Science in the Ancient and Medieval near East in Honor of E.S. Kennedy: Published Date: Book Condition: Very good: Jacket Condition: No Dustjacket: Binding: Paperback: Size: 8vo: Place of Publication: New York: Edition: First edition: Category: Science: Author: David A. King. Placement. The equant point (shown in the diagram by the large •), is placed so that it is directly opposite to Earth from the deferent's center, known as the eccentric (represented by the ×). A planet or the center of an epicycle (a smaller circle carrying the planet) was conceived to move at a constant angular speed with respect to the equant. In other words, to a hypothetical observer. Book-Review - from Deferent to Equant - History of Science in the Ancient and Medieval Near East in Honor of Kennedy, E.S.
Placement. The equant point, indicated in the diagram by the large •, is placed so that it is directly opposite the Earth from the center of the deferent (known as the "eccentric"), indicated by the X.A planet or the center of an epicycle (a smaller circle carrying the planet) was conceived to move with a uniform angular speed with respect to the equant. Claudius Ptolemy refined the deferent-and-epicycle concept and introduced the equant as a mechanism for accounting for velocity variations in the motions of the planets. The empirical methodology he developed proved to be extraordinarily accurate for its day . The epicycle rotated and revolved along the deferent with uniform motion. However Ptolemy found that the rate at which the deferent revolved was not constant unless he measured it from another point at an equal distance from the eccentric, which he called the equant. It was the angular rate at which the deferent moved around the equant that was. Buy From Deferent to Equant: A Volume of Studies in the History of Science in the Ancient and Medieval Near East in Honor of E.S. Kennedy on .
