Hipparchus was a Greek astronomer who lived between 190-120 B.C. He is considered the father of trigonometry, a branch of mathematics which studies the angles of sides of triangles. Hipparchus also developed the first accurate star map. It included over 850 stars, as well as descriptions of their brightness. |
Hipparchus was a Greek astronomer who lived between 190-120 B.C. He created the first accurate star map and kept a catalogue of over 850 stars with their relative brightnesses. He also developed the system of epicycles (where everything in space moved in perfect circles) for the planets that both agreed with observation, and preserved the Earth-centered universe of Aristotle. Hipparchus compiled a table of chord lengths, similar to modern trigonometry tables, and is considered the founder of trigonometry, a branch of mathematics which studies the angles of sides of triangles. |
Hipparchus was a Greek astronomer who lived between 190-120 B.C. He created the first accurate star map and kept a catalogue of over 850 stars with their relative magnitudes. The system of epicycles describing planetary motion was developed by Hipparchus, and helped preserve the geocentric model of the universe. His estimates of the moon's size and distance relative to Earth were also remarkably accurate for his time. Hipparchus is considered the founder of trigonometry for his work with the lengths of chords traced out by angles in a circle. His table of chords was the forerunner to modern trig tables. |
