This Tycho Brahe page and, in fact, the entire website are excerpted from You and the Universe, a handmade, individualized fine art book on astrology, mythology and astronomy through which the recipient's complete astrological reading is woven.

Tycho Brahe (1546-1601), an eccentric from a rich Danish noble family, soon followed. Fascinated by astronomy but disappointed with the accuracy to which planetary positions were then known, Tycho dedicated his life to recording planetary positions ten times more accurately than had ever been done before. This was brought within his grasp by the king of Denmark’s having given him an island with many families on it and money to build an observatory out of gratitude for Tycho’s uncle having saved his life. (One estimate puts the king’s gift at 10% of Denmark’s gross national product at the time!) On his island observatory/kingdom of Uraniborg Tycho built vast instruments with many clocks to take accurate sightings on stars, and particularly of the planet Mars.

In 1572 Tycho saw a new star being born in the heavens, and 32 years later his assistant Kepler, observed another supernova as well. These events were remarkable not only in their timing (the previous naked-eye supernova was observed in 1181 AD and the next is yet to be seen!), but because they also directly contradicted Aristotle, who had said that all changes in the heavens must take place in the lunar sphere close to Earth, and that the distant sphere of fixed stars was inviolate and unchanging.

Tycho reasoned, as had Aristotle before him, that nearby stars would show a shift against more distant background stars when viewed from opposite or distant points in the Earth’s orbit IF the Earth revolved around the Sun. Because he could not detect any such shift or "stellar parallax" in any star, he rejected Copernicus’ heliocentric model. It never occurred to him that the stars might be too far away for a stellar parallax to be seen with the naked eye.

In 1672 Giovanni Cassini used a parallax base line from Paris to Cayenne, French Guiana to measure the distance to Mars, and in so doing measured the Earth-Sun distance (1 AU) for the first time. It wasn’t until 1835, however, that Friedrich Bessel obtained the first accurate measurement of a star’s parallax for the star 61 Cygni. With a parallax of 0.32 arc-seconds (1/7200th of a degree), its parallax was more than 100 times below the threshold of Tycho Brahe’s ability to measure.