During this same period, Johannes Kepler was laboring on his greatest work, Epitome Astronomiae Copernicanae (Epitome of Copernican Astronomy), which was finally published in 1621. This publication tied together all of his previous work. This book, the first astronomy textbook based on the Copernican model, became the primary astronomical text for many years to follow.
The last major tome published during Johannes Kepler's life was Tabulae Rudolfinae (Rudolfine Tables), which appeared in 1625. This work was based on observations and calculations of Tycho Brahe. With these new tables of planet motion the mean errors of a planet's actual position were reduced from 5° to within 10'. Later, Sir Isaac Newton utilized Kepler's theories and observations in formulating his theory of gravitational force.
Johannes Kepler died on November 15, 1630, in Regensburg (now part of Germany).
Four years after his death, Somnium (Dream), was published. In this work, he described a journey to the Moon and spoke of lunar inhabitants. So, besides his voluminous contributions to astronomy and mathematics, Johannes Kepler was also one of the first science fiction writers.
