About Rømer
Ole Rømer made significant contributions to the field of temperature measurement.
He was a Danish astronomer known for his work in the late 17th century. The Rømer scale (also known as the Danish scale) was based on the freezing and boiling points of water as many temperature scales are. Rømer's scale used the freezing and boiling reference points as 0 degrees and 60 degrees respectively. While the Rømer scale is no longer used it played a role as an early precursor to the Celsius scale.
About Celsius
Celsius is the most commonly used temperature scale in the world. The Celsius scale (known as the centigrade in some instances) is named after the Swedish astronomer Anders Celsius. It is based on the freezing and boiling points of water at standard atmospheric pressure making 0°C the freezing point and 100°C the boiling point.
The Celsius scale is normally found in weather forecasts, household temperatures and cooking in most countries with the notable exception of the United States.