What are principle of heliocentric and the geocentric?

Answer 1

The geocentric principle has the Earth at the centre, while the heliocentric principle has the Sun at the centre. Modern theories of the solar system have the Sun at the centre and so are heliocentric.

The earliest theories of the movement of planets among the 'fixed' stars were based on a geocentric system in which the planets moved along circles and epicycles. Copernicus's heliocentric theory also used circles and epicycles and it was seen as a parallel explanation of the planets' movements.

Later Kepler used the heliocentric principle in his calculations, which were based on new and accurate measurements by Tycho Brahe. He discovered subtle effects which had previously not been noticed, that could only be explained by assuming that the planets move in elliptical orbits, and this led to his publication of the three Laws of Planetary Motion in 1609.

Answer 2

The earliest (recorded) statement that the Sun might be the center of the solar system was by the Greek astronomer and mathematician Aristarchus of Samos, in about 280 BCE. The actual writings by Aristarchus have not survived, but a later book called "The Sand Reckoner" by Archimedes refers to it. It's possible that someone came up with the idea earlier; but this is the earliest known expression of the heliocentric theory.

Alas, the "wrong-est man in history" Aristotle had his ideas more widely accepted for the next 1800 years.

Answer 3

geocentric