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Story Time: Johannes Kepler and Kelvin

Updated Feb 17, 2017 09:32am

To Johannes (John) Kepler, the world of science, nay, the world of the human mind, owes so heavily that it can never, try as it may, repay the debt. Born in Wurttemberg, Swabia, Germany of the Holy Roman Empire(1571-1630), he was a sickly child, with hands crippled from small-pox and eyes rendered so weak that he could not spot a person from a few yards away. His father was a poorly paid mercenary who died in a battle while on an expedition in the Netherlands. But his mother, Catherine, stood by him to the last, despite their backbreaking poverty.

I was so moved by his plight and the unending chain of miseries and misfortunes that I was often moved to tears as I read about his life over the years. Poorest among astronomers ever, he was also among the greatest despite his handicaps. In his latter-day life, misfortunes multiplied with the end of his miseries nowhere in sight.

First Kepler lost his favourite eight-year old son, which broke his heart. Then, his mother, who made a small living from herbal healing, was charged with witchcraft and despite her denials, was punished by Inquisition (again!) to be packed into a wooden box and lowered into a shallow grave at dusk and hauled out in the mornings for eight agonising years! Kepler’s pleadings finally saved her from what would have been a horrible end.

You will notice from one look at Kepler’s hapless life that few in our times can match up to his intrepidity and perseverance. Yet, besides being an astronomer par excellence, he was a mathematician of great merit. Nothing daunted him or could stand in his way.

Most notable of Kepler’s achievements are the laws of planetary motion. Before that, we must give credit to the Danish astronomer, Tycho Brahe (1546-1601), who was given an island (and its revenue) as a gift to carry on with his observational work. The island was called Hven, and the institute he built thereon was named Uraniburg.

He employed Kepler and left his loads of accurate and highly dependable observations of planets to him. The data thus bequeathed to him served him in good stead after Tycho’s death. It must be kept in mind that Tycho was the greatest observational astronomer of the pre-telescope era, working with his eyes alone and the voluminous data accumulated over the years.

Kepler’s laws of planetary motion, (of which many of you are already aware), are:

  1. The planets move around the Sun in elliptical paths, much like an egg (not circular), with the Sun at one focus (end) and the other focus empty.

  2. The line connecting the planet to the Sun, sweeps out equal areas in equal times. For instance, in one month the Sun travels as much as in any other one month, roughly, that is.

  3. The square of the periods in which the planets describe their orbits are proportional to the cubes of their average distances from the Sun.

As I had stated in an earlier article, the last of the Laws is a bit difficult to understand, but that is the way astronomy is in a few instances. But not many, I assure you.

As we come to the end of the immortal Kepler’s story let us not forget that he was one of the fathers of astronomy, and that of the Renaissance, 13th to 16th century Europe and, consequently, the world.

Kelvin Scale: A unit of temperature based on the scale where zero point equals -273.16 Celsius, called absolute zero, or zero Kelvin.

Named after the British scientist Lord Kelvin (1823-1907), the scale has the freezing point of water as 273 degrees Kelvin and the boiling point is 373 degrees Kelvin.

One advantage of this scale is the elimination of plus or minus signs as all temperatures begin at absolute zero.

It may be noted that absolute zero is absolutely unattainable anywhere in any laboratory. It always falls fractionally short. This scale is used in most sciences, above all in astronomy.

Published in Dawn, Young World, February 11th, 2017