Bologna, Italy (June 23, 2014). In the decade after Galileo was placed under house arrest (in 1632), the church had come to a realization that it made a mistake. Church leaders needed to make predictions that depended on knowing several important astronomical facts. In particular, they needed to know exactly how long the year was, and whether the sun moved across the sky at varying speeds. The latter problem would help answer the question of whether the seasons were exactly equal. In addition, Kepler had already introduced the idea that orbits might be elliptical instead of circular, and this created the need to know exactly how far the sun was from the Earth at various points of the year.
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The Meridian Line in San Petronio Basilica, Bologna. At noon the sun
crosses this line. It crosses at different points during the year. |
Now, if Galileo and Kepler were heretical -- and their hypotheses incorrect -- then there would be no reason to ask these questions. And, there would be no reason to place solar-observing instruments in churches in Bologna and elsewhere. Yet, they did. The meridian line in San Petronio was installed first in 1648 (but not corrected for accuracy until twenty years later).
Such was the background for a week-long course and sightseeing trip to Emilia Romagna with two of Cornell's most distinguished professors, Martha Haynes and Riccardo Giovanelli. (More to follow...)
