Friday, December 31, 2010

The first earth shaker: Copernicus

Let's continue our exploration of the birth of modern science ...

Since early history the scientists who studied the heavens were the only scholars to use mathematics, and the terms astronomer, astrologer and mathematician were virtually interchangeable. They calculated the dates of the holy days, developed methods to draw astrological charts, and forecast the position of the zodiac signs and the movement of the planets. However, despite their skillful observations, measurement and calculations, many open issues remained unanswered, some unquestioned. Their theories could not account for the changes in the brightness of the planets, nor for their apparent retrograde movement (at times some planets seem to move backwards.) Their models did not explain why Venus and Mercury were never seen far from the sun, and they could not even agree on the order of the planets. They did calculations, and it was not their role to ponder such matters. How the world worked was a theological question that only the Church was allowed to answer.

All this changed in 1514 when a Polish astronomer, Nicolaus Copernicus (1473-1543) circled amongst a few of his friends an unsigned hand-written book called Little Commentary. In his book, Copernicus introduced the heliocentric model, in which the sun  – rather than the earth – was at the center of the universe and all planets, including earth, were orbiting around it. With a single model Copernicus explained the apparent movement of the planets, the sun and the stars. His model could also account for the changes in the brightness of the planets, and offered a singular method of ordering them. Copernicus also managed to calculate  the relative distances of the planets from the sun with amazing accuracy (his figures showed less than 10% difference from our current measurements.) However, Copernicus knew that  all the advantages of his model would not protect him from the hostility of the orthodox authorities and the Inquisition. It was not until 1543 – the year of his death – that he eventually published his complete work On the Revolutions of the Heavenly Spheres.

Sunday, December 5, 2010


People take the lift to use the Stairmaster in the gym on the 14th floor. Why don’t they use the stairs to the gym instead?