Theory put beauty before physics

It took scholars a long time to accept Nicholas Copernicus's claim that the Sun and not the Earth sat at the heart of the solar system. But analysis by Owen Gingerich, a historian at Harvard-Smithsonian Center for Astrophysics, in the US, suggests this was due less to stubborn short-sightedness than to the time it took technology to provide the evidence to match the Polish astronomer's vision.

With the benefit of hindsight, it might seem remarkable that Copernicus's expulsion of the Earth from the centre of the universe in 1543 had few adherents for almost a century.

Professor Gingerich's study, presented to the American Physical Society, shows that the astronomer had been motivated by aesthetics rather than new observations and that the mathematical fudges his new system needed to explain the exact motions of the heavens hardly made it more compelling than what it sought to replace.

"There were no observations specifically driving Copernicus to a heliocentric system. Essentially, to him it was beautiful because it provided a natural explanation as to why planets went into retrograde motion and that kind of aesthetic over-rode the lack of a proper physics," said Professor Gingerich.

"One reason it took so long for the heliocentric system to be adopted is that even if you found the aesthetics of it very interesting, you still didn't find any empirical evidence on its behalf."

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