Tycho Brahe

Tycho Brahe: see Brahe, Tycho.

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Brahe, Tycho 

Born Dec. 14, 1546, in Knudstrup; died Oct. 13, 1601, in Prague. Danish astronomer.

In 1572, Tycho observed a new star in the constellation Cassiopeia. From 1576 to 1597 he directed the Uraniborg Observatory, which he built on the island of Hven in Øresund Strait near Copenhagen and equipped with excellent instruments made under his supervision. He spent 21 years there observing the stars, planets, and comets and determining the positions of heavenly bodies with a very high degree of accuracy. This was his main contribution. He also discovered two inequalities in the motion of the moon (annual inequality and variation). He demonstrated that comets are heavenly bodies farther from the earth than the moon. He compiled refraction tables. Tycho did not accept the heliocentric system of the world; in its place he proposed another system (that the sun moves around the earth, the earth stands in the center of the universe, and the planets revolve around the sun); this was an unsuccessful combination of Ptolemy’s teaching and the Copernican system. In 1597, Tycho was forced to leave Denmark (the Uraniborg Observatory was abandoned after his departure); and after spending two years in Germany, he went to Prague, where J. Kepler became his assistant. Kepler was left very valuable observations after Tycho’s death. Based on these observations, Kepler formulated his famous laws of the motion of the planets.

WORKS

Opera omnia, vols. 1–15. Edited by J. L. E. Dreyer. Copenhagen, 1913–29.

REFERENCES

Berry, A. Kratkaia istoriia astronomii, 2nd ed. Moscow-Leningrad, 1946. (Translated from English.)
Dreyer, J. L. E. Tycho Brahe. Edinburgh, 1890.
Tycho Brahe’s Description of His Instruments and Scientific Work. Translated and edited by H. Raeder (and others). Copenhagen, 1946.