Celsius Temperature ScaleThe Celsius temperature scale is also referred to as the centigrade scale. Centigrade means "consisting of or divided into 100 degrees". The Celsius scale, invented by Swedish Astronomer Anders Celsius (1701-1744), has 100 degrees between the freezing point (0 C) and boiling point (100 C) of pure water at sea level air pressure. The term "Celsius" was adopted in 1948 by an international conference on weights and measures.
Anders CelsiusAnders Celsius was born in Uppsala, Sweden in 1701, where he succeeded his father as professor of astronomy in 1730. It was there that he built Sweden's first observatory in 1741, the Uppsala Observatory, where he was appointed director. He devised the centigrade scale or "Celsius scale" of temperature in 1742. He was also noted for his promotion of the Gregorian calendar, and his observations of the aurora borealis. In 1733, his collection of 316 observations of the aurora borealis was published and in 1737 he took part in the French expedition sent to measure one degree of meridian in the polar regions. In 1741, he directed the building of Sweden's first observatory.
One of the major questions of that time was the shape of the Earth. Isaac Newton had proposed that the Earth was not completely spherical, but rather flattened at the poles. Cartographic measuring in France suggested that it was the other way around - the Earth was elongated at the poles. In 1735, one expedition sailed to Ecuador in South America, and another expedition traveled to Northern Sweden. Celsius was the only professional astronomer on that expedition. Their measurements seemed to indicate that the Earth actually was flattened at the poles.
Anders Celsius was not only an inventor and astronomer, but also a physicist. He and an assistant discovered that the aurora borealis had an influence on compass needles. However, the thing that made him famous is his temperature scale, which he based on the boiling and melting points of water. This scale, an inverted form of Celsius' original design, was adopted as the standard and is used in almost all scientific work.
Anders Celsius died in 1744, at the age of 42. He had started many other research projects, but finished few of them. Among his papers was a draft of a science fiction novel, situated partly on the star Sirius.