Anders Celsius died on this day 280 years ago, aged 42.
- Celsius' family was full of scientists- his uncle Olof was a botanist, his paternal grandfather Magnus was a mathematician, and his maternal grandfather Anders Spole was an astronomer. His father Nils was also a professor of astronomy at Uppsala University, which he would attend- and also became an astronomy professor there in 1730.
- Celsius had several feats in the realm of astronomy: he was the first person to link auroras with changes in the Earth's magnetic field (based on observations within a compass), and he participated in an expedition that proved the world was an ellipsoid and not a perfect sphere.
- Celsius was most famous for his temperature scale, centigrade, which he proposed in 1742. It is now the dominant temperature scale in the world (three countries use Fahrenheit instead), and Celsius' name has been used interchangeably with 'centigrade'.
- Celsius' young death was caused by a bout of tuberculosis.