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Though Copernicus’s work was
widely circulated, it took a century
or more before its basic ideas
were accepted by most other
astronomers, let alone the public
at large. One difficulty was that,
although it resolved many of the
problems of the Ptolemaic system,
his model also contained faults
that had to be amended by later
astronomers. Many of these faults
were due to the fact that, for
philosophical reasons, Copernicus
clung to the belief that all the
movements of celestial bodies
occurred with the objects
embedded in invisible spheres
and that these movements must
be perfect circles. This therefore
forced Copernicus to retain some
of Ptolemy’s epicycles in his model.
The work of Johannes Kepler
later replaced the idea of circular
orbits with that of elliptical orbits,
eliminating most of the remaining
faults in Copernicus’s model. It
wasn’t until the 1580s and the
work of Danish astronomer Tycho
Brahe that the idea of celestial
spheres was abandoned in favor
of free orbits.Banned by the Church
De revolutionibus initially met
with little or no resistance from
the Roman Catholic Church,
although some Protestants
denounced it as heretical. In 1616,
however, the Catholic Church
condemned Copernicus’s book and
it remained proscribed reading for
more than 200 years. The Church’s
decision coincided with a dispute it
was having at the time with the
astronomer Galileo Galilei. Galileo
was an avid champion of the
Copernican theory and had made
discoveries in 1610 that strongly
supported the heliocentric view.
The dispute with Galileo caused
the Church authorities to examine
De revolutionibus with intense
scrutiny, and the fact thatFROM MYTH TO SCIENCE
Mars’s apparent retrograde motion
occurs about every 26 months and
lasts for 72 days. Its orbit is on a
slightly different plane from Earth’s,
contributing to the apparent loop.some of its propositions went
against Biblical texts probably
led to the ban.
Viewed somewhat ambivalently
at first by astronomers, and
prohibited by the Catholic Church,
Copernicus’s heliocentric model
therefore took considerable time
to catch on. Several centuries
passed before some of its basic
propositions were demonstrated
to be true beyond dispute: that
Earth moves in relation to the
stars was eventually proved
conclusively by English astronomer
James Bradley in 1729. Proof that
Earth spins came with the first
demonstration of Foucault’s
pendulum in 1851.
Copernicus’s theory was
a serious blow to old ideas
about how the world and wider
universe work—many of them
dating from the time of Aristotle.
As such, it is often cited as
ushering in the “Scientific
Revolution”—a series of sweeping
advances in many areas of science
that occurred between the 16th
and 18th centuries. ■I am deterred by the fate of
our teacher Copernicus who,
although he had won immortal
fame with a few, was ridiculed
and condemned by countless
people (for very great is the
number of the stupid).
Galileo Galilei