Units of Measurement/Temperature

The SI unit for Temperature is the Kelvin (K). However, Celsius (°C) is also often used as a measure of temperature. The formula to convert Celsius to Kelvin is K = °C + 273.15, so 25 °C will equal to 298.15 K. 25 degrees Celsius or 298.15 Kelvin is called room temperature, and 0 °C or 273.15 K is called standard temperature. Fahrenheit (°F) is also a commonly used temperature system in the United States, and the formula to convert from Celsius to Fahrenheit is F= C*1.8+32. An example would be 32 Celsius times 1.8 is 57.6, and then gets added with 32 to make 89.6 °F.

There are also scales like the Rankine scale, which is the Kelvin version of Fahrenheit, or the Delisle scale that has negative numbers correspond to warmer temperatures.

Common Temperatures
0 K | -273.15 °C | -458.67 °F is the temperature needed to make absolute zero, the lowest temperature that can theoretically exist. However, it is impossible to get to this temperature as Heisenberg's Uncertainty Principle states that we can know the position or velocity of a particle, but not both. Absolute zero would allow us to know both, which would be impossible.

1 K | -272.15 °C | -457.87 °F is how cold the Boomerang Nebula is, making it the coldest known natural place in the universe.

4.25 K | -268.90 °C | -452.07 °F is the boiling point of helium at standard pressure. 

273.15 K | 0 °C | 32 °F is the melting point of pure water, and is also standard temperature.

373.15 K | 100 °C | 212 °F is the boiling point of pure water.

5811.3 K | 5537.8 °C | 10000 °F is the average temperature of the sun's photosphere.