Anders Celsius

Anders Celsius was born November 27, 1701 in Sweden.
His areas of interest: astronomy, general physics, geophysics.

He taught astronomy at Uppsala University, founded the astronomical observatory.

Celsius first measured the brightness of stars, the interconnection between the northern lights and vibrations in the Earth's magnetic field.

He took part in the Lapland expedition 1736-1737 period to measure the meridian. On his return from the polar regions Celsius started active work on organization and construction of an astronomical observatory in Uppsala and in 1740 became its director.

In 1742, he proposed 100-degree thermometer scale in which zero degrees is taken to the boiling point of water at normal atmospheric pressure, and for 100 degrees - the temperature of melting ice (now vice versa!). Division of the scale is 1 / 100 of the difference.

We use the international practical temperature scale set by the International Committee of Weights and Measures is predicated on the principles of Celsius and Kelvin.

Anders Celsius died March 25, 1744.

In his honor, called the mineral "tselzian - barium feldspar composition Ba [Al2Si2O8], impurity K, Ca and Sr. Tselzian crystallizes in the monoclinic system: structure, regulation and forms of selection - as in other K-Na feldspars. Density 3300-3400 kg/m3; hardness mineralogical scale 6-6.5. Tselzian colorless. Rare. Tselzian usually occurs in the contact-metasomatic deposits, manganese-rich rocks. Found in the Ukraine, Sweden, Japan and other countries.