Sentence examples for deferent from inspiring English sources

Astronomers remarked that the eccentric orbit representing the Sun's annual motion could be replaced by a pair of circles, a deferent centred on the Earth and an epicycle the centre of which moved along the circumference of the deferent.

In the Ptolemaic system each planet revolves uniformly along a circular path (epicycle), the centre of which revolves around the Earth along a larger circular path (deferent).

The centre of the deferent was located midway between the equant and the Earth, as can be seen in the figure.

Ptolemy enhanced the effect of eccentricity by making the epicycle's centre sweep out equal angles along the deferent in equal times as seen from a point that he called the equant.

In order to account for phenomena arising from the Earth's motion around the Sun, the Ptolemaic system included a secondary circle known as an epicycle, whose centre moved along the path of the primary orbital circle, known as the deferent.

Apollonius introduced an alternative "epicyclic" model, in which the planet turns about a point that itself orbits in a circle (the "deferent") centred at or near the Earth.

Because one half of an epicycle runs counter to the general motion of the deferent path, the combined motion will sometimes appear to slow down or even reverse direction (retrograde).

By varying the relative sizes and rotation rates of the epicycle and deferent, in combination with the eccentric, a flexible device may be obtained for representing planetary motion.

The vesicles are close together in their lower parts, but they are separated above where they lie close to the deferent ducts.

A second tradition, deriving from Claudius Ptolemy, solved this problem by postulating three mechanisms: uniformly revolving, off-centre circles called eccentrics; epicycles, little circles whose centres moved uniformly on the circumference of circles of larger radius (deferents); and equants.

Each time that astronomers encountered new difficulties -- like explaining the retrograde motion of Mars, Jupiter and Saturn -- they developed highly creative new concepts like epicycles and deferents.