Hipparchus

American  

[hi-pahr-kuhs] / hɪˈpɑr kəs /

noun

1. died 514 b.c., tyrant of Athens 527–514.

2. c190–c125 b.c., Greek astronomer.

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Hipparchus ¹ British  

/ hɪˈpɑːkəs /

noun

1. a large crater in the SW quadrant of the moon, about 130 kilometres in diameter

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Hipparchus ² British  

/ hɪˈpɑːkəs /

noun

1. 2nd century _bc , Greek astronomer. He discovered the precession of the equinoxes, calculated the length of the solar year, and developed trigonometry

2. died 514 _bc , tyrant of Athens (527–514)

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Hipparchus Scientific  

/ hĭ-pär′kəs /

1. Greek astronomer who mapped the positions of about 850 stars in the earliest known star chart (129 bce). His observations of the heavens formed the basis of Ptolemy's Earth-centered model of the universe. He was also a pioneer of trigonometry.

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Example Sentences

See Examples For:

Hipparchus

Among other things, it was Hipparchus himself who first discovered Earth’s precession, and he modelled the apparent motions of the Sun and Moon.

From Scientific American ● Oct. 20, 2022

Evans says it proves that Hipparchus, often considered the greatest astronomer of ancient Greece, really did map the heavens centuries before other known attempts.

From Scientific American ● Oct. 20, 2022

The researchers were able to use this to check when the ancient astronomer must have made his observations, and found that the coordinates fit roughly 129 BC—during the time when Hipparchus was working.

From Scientific American ● Oct. 20, 2022

Today, it is our main source of information about the work of Hipparchus and other Greek astronomers.

From Textbooks ● Oct. 13, 2016

The figures, from left to right, are the astronomers Hipparchus, Copernicus, an anonymous ancient observer, Brahe and Ptolemy, each surrounded by symbols of his work.

From "The Invention of Science" by David Wootton