the epicycle is not a linear function of the angle of the deferent. In the Hipparchian system the epicycle rotated and revolved along the deferent with...

backward in retrograde motion, and then again reversed to resume normal, or prograde, motion. The deferent-and-epicycle model had been used by Greek astronomers...

retrograde motion was explained by having the planets travel in deferents and epicycles. It was not understood to be an illusion until the time of Copernicus...

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...

{R+r}{r}}\theta \right)} List of periodic functions Cycloid Cyclogon Deferent and epicycle Epicyclic gearing Epitrochoid Hypocycloid Hypotrochoid Multibrot...

Russell's teapot Deferent and epicycle § Bad science No true Scotsman Special pleading The Structure of Scientific Revolutions Proofs and Refutations "The...

Greek concepts of deferent and epicycle in the Ptolemaic system of astronomy were related to Fourier series (see Deferent and epicycle § Mathematical formalism)...

theory of eccentrics and epicycles (and their deferents). This was further elaborated on by Hipparchus in the second century BC and, later, by Ptolemy in...

against the background of stars. The ecliptic is an important reference plane and is the basis of the ecliptic coordinate system. The ecliptic is the apparent...

axis and its orbital axis, which is the line perpendicular to its orbital plane; equivalently, it is the angle between its equatorial plane and orbital...

Apollonius of Perga (c. 262 – c. 190 BC) had introduced the deferent and epicycle and the eccentric deferent to astronomy. Hipparchus (2nd century BC) had crafted...

of the planets, a system of deferents and epicycles was used. The planet was said to revolve in a small circle (the epicycle) about a center, which itself...

Roulettes Centered trochoid Epitrochoid Epicycloid Cardioid Nephroid Deferent and epicycle Hypotrochoid Hypocycloid Astroid Deltoid curve Topology Borromean...

and Mihira were a father-son duo at Vikramaditya's court, and the poet Khana was Mihira's wife. This legend is of no historical value. "Varaha" and "Mihira"...

Earth, Moon, Sun, planets and unseen "counter-earth" revolve around an unseen "Central Fire" was developed in the 5th century BC and attributed to the Pythagorean...

the planets are each governed by two epicycles, a smaller manda (slow) epicycle and a larger śīghra (fast) epicycle. It has been suggested by some commentators...

Earth): 3144 : 327+2⁄3; and for the epicycle model, the ratio between the radius of the deferent and the epicycle: 3122+1⁄2 : 247+1⁄2 . These figures...

where it is known as Aippasi, and the solar Indian national calendar. It is the sixth month of the solar Bengali calendar and the seventh of the lunar Indian...

is produced by a combination of a deferent and two epicycles. The centre of the first, and larger of the two epicycles, represented by the point e1 in the...

quadrilateral Cycloid Epitrochoid Epicycloid Cardioid Nephroid Deferent and epicycle Ex-tangential quadrilateral Horocycle Hypotrochoid Hypocycloid Astroid...

features the world's largest stone sundial, and is a UNESCO World Heritage Site. It is near City Palace and Hawa Mahal. The instruments allow the observation...

Siddhanta etc. Sidereal astrology maintains the alignment between signs and constellations via corrective systems of Hindu (Vedic)-origin known as ayanamsas...

it is called Bohag) and the Bengali calendar (where it is called Boishakh). This month lies between the second half of April and the first half of May...

morning. Devotees usually go to temples early in the morning and recite Thiruppavai by Andal and Thiruvempavai by Manikkavacakar. Hinduism portal Astronomical...

\omega _{-}} and the modified cyclotron ω + {\displaystyle \omega _{+}} frequencies. These motions are similar to the deferent and epicycle, respectively...

was the need for deferents and epicycles abolished. In his work, Copernicus "used conventional, hypothetical devices like epicycles...as all astronomers...

apparent construction date of the mechanism—carried forward with more epicycles, and was more accurate predicting the positions of planets than the view...

Ptolemy's deferent and epicycle model. Aristotle submits to the calculations of astronomers regarding the total number of spheres and various accounts give...

observatory was to compile astronomical tables, and to predict the times and movements of the sun, moon and planets. Some of these purposes nowadays would...

to explain the complex motions of the planets, a device known as deferent and epicycle first developed by Apollonius of Perga. Published in the Almagest...