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Hipparkh

Picture of Hipparkh

Place of birth: Nikea

Nationality: Greece

Background

Hipparchus (about 190-125 BC) - ancient Greek scientist, one of the founders of astronomii.Rodilsya in the city of Nicea, he lived and worked in Alexandria, on the island of Rhodes. Hipparchus is credited with creating the first mathematical theories apparent motion of the sun and the moon and eclipses the theory. He correctly identified the size of the Moon and its distance from the Earth. Comparing the results of personal observations and the observations of his predecessors, he very accurately calculated the length of the solar year (the error is not more than 6 minutes).

Hipparchus and other ancient astronomers paid much attention to the observations of planetary motions.

The observed motion of the planets from the Earth is quite difficult: the speed of the planet increases and decreases, and at times it does stop, then begins to move in the opposite direction. This planet is sometimes described in the loop sky. This complexity as we now know, is the result of what is observed from Earth, which itself revolves around the sun.

Hipparchus also, who believed the Earth immobile, believed the observed motion of the planets real. In explaining the motion of the planets, he followed the theory of epicycles. The theory of epicycles gave a certain approximation purely formal, geometric representation of the motion of the planets.

Hipparchus compiled a table of the provisions of the Sun and Moon allowed precalculate moments occurrence error 1-2 ch.pparh was first used in astronomy methods of spherical trigonometry. He increased the accuracy of observations, using the crosshairs for aiming the light in goniometric instruments - sextants and quadrants.

The scientist was huge at the time the catalog of positions 850 stars, dividing them on shine into 6 degrees (magnitudes).

Hipparchus introduced the geographical coordinates - latitude and longitude, and it can be considered the founder of mathematical geography.