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

The first person we know did this was Greek polymath Hipparchus, who created a star map noting the brightness of various stars more than two millennia ago.

From Scientific American • Jul. 28, 2023

The discovery “enriches our picture” of Hipparchus, says Evans.

From Scientific American • Oct. 20, 2022

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

Almagest does not deal exclusively with Ptolemy’s own work; it includes a discussion of the astronomical achievements of the past, principally those of Hipparchus.

From Textbooks • Oct. 13, 2016

Hipparchus anticipated that stars come into being, slowly move during the course of centuries and eventually perish; it was he who first catalogued the positions and magnitudes of the stars to detect such changes.

From "Cosmos" by Carl Sagan