What is Hipparchus table of chords?
What is Hipparchus table of chords?
Hipparchus (190–120 B.C.E.) produced the first trigonometric table for use in astronomy. It was a table of chords for angles in a circle of large fixed radius. Incidentally, his table was not in terms of degrees, but “steps”, each step being 1/24 of a circle.
What was Hipparchus most famous for?
Solar and lunar theory. Hipparchus’s most important astronomical work concerned the orbits of the Sun and Moon, a determination of their sizes and distances from Earth, and the study of eclipses.
What is the theory of Hipparchus?
Hipparchus discovered the precession of the equinoxes and observed the appearance of a new star – a nova. He suspected stars might move slowly with respect to one another over great lengths of time; he hoped people living in the future could verify this.
What did Hipparchus discover?
Hipparchus. Hipparchus, (b. Nicaea, Bithynia–d. after 127 BC, Rhodes?), Greek astronomer and mathematician who discovered the precession of the equinoxes, calculated the length of the year to within 6 1/2 minutes, compiled the first known star catalog, and made an early formulation of trigonometry.
How did Hipparchus discover trigonometry?
He did this by using the supplementary angle theorem, half angle formulas, and linear interpolation. Hipparchus was not only the founder of trigonometry but also the man who transformed Greek astronomy from a purely theoretical into a practical predictive science.
Who is the father of trigonometry in India?
Aryabhata I
In India, the father of trigonometry is Aryabhata I, also known as the father of zero. He is an Indian mathematician and astronomer. Aryabhata gathered and elaborated the improvements of the Siddhantas points in path-breaking literature, the “Aryabhatiya”. The first table of sines is given in the Aryabhatiya.
When did Hipparchus rule?
Hipparchus (Greek: Ἵππαρχος Hipparchos; died 514 BC) was a member of the ruling class of Athens. He was one of the sons of Pisistratus. He was a tyrant of the city of Athens from 528/7 BC until his assassination by the tyrannicides, Harmodius and Aristogeiton in 514 BC.
How did Hipparchus measure the distance to the moon?
Hipparchus used observations from a total eclipse of the Sun to estimate the distance of the Moon from the Earth. The eclipse he used was total at the Hellespont (the narrow strait that separates the European and Asian parts of Turkey) but only part of the Sun was seen covered from Alexandria, in Egypt.