Explanation:
Discovered by accident, this manuscript page
provides graphical insight to astronomy in
medieval times, before the
Renaissance and the influence of
Nicolaus Copernicus,
Tycho de Brahe,
Johannes Kepler, and
Galileo.
The intriguing page is from the lecture notes
on astronomy compiled by the monk Magister Wolfgang de Styria
before the year 1490 at Melk Abbey in Austria.
The top panels clearly illustrate the necessary geometry for a
lunar (left) and solar eclipse in the Earth-centered
Ptolemaic system.
At lower left is a diagram of the
Ptolemaic view of the solar system
and at the lower right is a chart to calculate the
date
of Easter Sunday in the
Julian calendar.
Text at the upper right explains the
movement
of the planets according to the Ptolemaic system.
The actual manuscript page is on view at historic
Melk Abbey
as part of a
special exhibition during the
International Year of Astronomy.
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