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Yes.
We now understand that all the planets travel round the Sun, and a planet's retrograde motion happens as the Earth overtakes the other planet in its orbit. The Earth goes round more quickly than all the outer planets from Mars onwards.
In Ptolemy's model the Earth is stationary in the centre, and the planets move on circles and epicycles.
Using Mars as an example and assuming the orbits of Earth and Mars are circular for simplicity, the Earth is at the centre and then Ptolemy's model has a circle (or deferent) round it with a radius of 1.524 units. The epicycle is a smaller circle whose centre travels round the deferent in 687 days. The epicycle has a radius of 1.000 units and Mars travels round this in 365 days.
That was Ptolemy's geometric construction to explain the motion of Mars, which it does pretty accurately, and the retrograde motion happens when Mars on its epicycle moves close to the Earth.
Ptolemy used additional epicycles to allow for what we now call eccentricity in Mars's orbit, and also for what we now understand is the orbit's inclination to the ecliptic.
What else can I help you with?
What was the date Saturn was discovered?
Saturn was discovered on March 25, 1610 by Galileo Galilei.
Convection currents discovered date?
convection currents discovery date
When is Mercury's Retrograde Expected?
Mercury has three - four retrograde periods each year. In 2016 Mercury is expected to go retrograde: January 5 to 25 April 28 to May 22 August 30 to September 22 December 19 to 31
What came first Ibn Idrisi's Ptolemy's or Piri Reis's world map?
well the piri reis map was created in 1929 and as for the ptolemy's map i am currently unable to find the creation date for it so the ptolemy's map came first because i am on a quiz and my teacher says it came first.
What is the date of Jupiters discovery?
Jupiter was discovered by Galileo on January 7, 1610.
What is the name given to the phenomenon in which the apparent motion of the planets sometimes reverses?
Retrograde motion happens when the Earth overtakes an outer planet in its orbit. It happens around the date of Opposition when the planet is opposite the Sun in the sky. Usually planets travel from west to east along the ecliptic, but during retrograde motion they travel backwards, from east to west,.
What is ptolemy date of birth?
900ad
When planets move western and then return the normals motion?
It is called retograde motion which occurs round the time of opposition (outer planets only). Normally planets appear to move from west to east, in other words if they are in one position on a certain date, they will be east of that position 365 days later. The far-off planets Uranus and Neptune move only a little way along the ecliptic each year: 4.3 degrees for Uranus and 2.2 degrees for Neptune. However, when the planets are at opposition (exactly opposite the Sun, so they are south at midnight), they appear to be moving backwards (east to west) as the Earth overtakes them in their orbit. This is called retrograde motion, when they appear to move east to west from one night to the next. It happens for a few days around opposition for all the outer planets. The early orbital models of Ptolemy and Copernicus were able to predict retrograde motion correctly.
What date was xenon discovered?
It was discovered in 1898.
What was the date Saturn was discovered?
Saturn was discovered on March 25, 1610 by Galileo Galilei.
What is the date Cleopatra's father died?
Cleopatra's father was Ptolemy XII and he died in 51 BC.
When was Vegemite discovered?
1922 was the date that vegemite was discovered
What date was homo erectus discovered?
He was discovered in 1891
What was the date of Ptolomy's death?
Ptolemy was a fairly common Macedonian name. A dynasty of that name ruled Egypt after Alexander's death. The last Ptolemy of that dynasty was Cleopatra, who suicided in 31 BCE.
Which Italian astronomer wrote The Theory of Planetary Motion in 1632?
Several astronomers wrote theories of planetary motion. Ptolemy's theories date to antiquity. Copernicus wrote his theories in the early 16th century. Kepler's theories were written in the early 17th century.
When was oxygen discovered and what date?
Oxygen was discovered by Joseph Priestley in 1774. The exact date is August 1, 1774.
Who discovered protactinium and what date did they discovered it?
Protactinium was discovered in 1913 by Fajans and Gohring in Karlsruhe, Germany.
