Anders Celsius is best known for the temperature scale that now bears his name. But this Swedish astronomer, physicist and mathematician did a lot more than just that. A.S.Ganesh eyes Celsius to a closer degree and hands you these details...

You’ve heard the word “Celsius” haven’t you? Be it in those weather reports when you are eagerly waiting for a day to be declared a holiday due to rains, or in the thermometer when your parents are trying to find out if your fever is too high, the temperature is always given in degree Celsius. But did you know that that word actually comes from Anders Celsius, the man who gave us this temperature scale?

Born in Uppsala, Sweden in 1701, Celsius followed his father, who was a professor of astronomy at the University of Uppsala. Celsius took to mathematics, astronomy and experimental physics, quickly rising to the position of secretary of the Uppsala Scientific Society in 1725. After teaching mathematics at the university for years, Celsius too was appointed professor of astronomy in 1730.

He travelled extensively from 1732 to 1736, broadening his knowledge and perspective by visiting other countries. He made it a point to visit astronomers and observatories when he was out on these trips, picking their brains and learning as he went.

Studies aurora borealis

One of his first contributions and research involved the study of the auroral phenomena. Along with an assistant, Celsius discovered that the aurora borealis had an influence on compass needles.

He had been tracking these extensively and in 1733, while visiting the observatory at Nuremberg, he published a collection of over 300 observations of the aurora borealis made by himself and others over more than 15 years.

His trips to Italy, Germany and France eventually took him to Paris, where he made the acquaintance of Pierre Louis Maupertuis, a French mathematician. Maupertuis was planning an expedition to measure a meridian in the north and Celsius joined in on this, paying visits to London to obtain necessary instruments.

Verifies Newtonian theory

The expedition was planned to disprove the Cartesian view and verify the contrary Newtonian theory that stated that the earth is flattened at the poles. In his capacity as an astronomer, Celsius was able to help with the planned meridian measurement, thereby confirming Newton’s theory.

On returning to Uppsala, Celsius was able to teach astronomy with a new-found vigour. He also generated enough interest and resources for the construction of an observatory in the place. Under his observation, the Uppsala Astronomical Observatory came into being in 1741 – the first modern installation of its kind in Sweden.

The centigrade scale

The thing that made him famous came about soon after. While there are suggestions that Celsius devised the scale on December 25, 1741, we can say for certain that a thermometer with this scale incorporated existed from 1742. The Celsius scale is also known as the centigrade temperature scale as it is divided into 100 equal gradients or degrees.

Even though other 100-degree scales had been used earlier, Celsius’ scale was the first one that led to its general acceptance. This was because Celsius experimented diligently in order to develop the scale. He was able to determine that water’s freezing point is independent of latitude and atmospheric pressure, whereas these factors affect the boiling point of water. He documented his experiments in “Observations of two persistent degrees on a thermometer.”

Interestingly, Celsius originally had 0 as the boiling point and 100 as the freezing point. Celsius did not live to see his scale become the standard as he died at the young age of 42 in 1744. The scales were reversed and introduced soon after in 1747 and the present system of the Celsius scale was born. Even though it was interchangeably called centigrade and Celsius scale, “Celsius” was officially adopted as the unit of measurement in 1948.