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===Astronomy===

===Astronomy===

Tycho was the preeminent observational astronomer of the pre-telescopic period, and his observations of [[star|stellar]] and [[planet]]ary positions achieved unparalleled accuracy for their time. For example, Tycho measured Earth's [[axial tilt]] as 23 degrees and 31.5 minutes, which he claimed to be more accurate than Copernicus by 3.5 minutes. After his death, his records of the motion of the planet [[Mars (planet)|Mars]] enabled Kepler to discover the [[Kepler's laws of planetary motion|laws of planetary motion]], which provided powerful support for the [[Copernican heliocentrism|Copernican heliocentric theory]] of the solar system.

Tycho was the preeminent observational astronomer of the pre-telescopic period, and his observations of [[star|stellar]] and [[planet]]ary positions achieved unparalleled accuracy for their time. For example, Tycho measured Earth's [[axial tilt]] as 23 degrees and 31.5 minutes, which he claimed to be more accurate than Copernicus by 3.5 minutes. After his death, his records of the motion of the planet [[Mars (planet)|Mars]] enabled Kepler to discover the [[Kepler's laws of planetary motion|laws of planetary motion]], which provided powerful support for the [[Copernican heliocentrism|Copernican heliocentric theory]] of the solar system.