Infrared light was discovered in 1800 by Sir Frederick William Herschel. Herschel, born in Hanover, Germany, decided to investigate the temperature of each color of the spectrum produced when sunlight is passed through a prism.To do this, he used three thermometers whose bulbs he blacked out (the better to absorb heat with).erschel, born in Hanover, Germany, decided to investigate the temperature of each color of the spectrum produced when sunlight is passed through a prism. To do this, he used three thermometers whose bulbs he blacked out (the better to absorb heat with).
Body temperature may be abnormal due to fever (high temperature) or hypothermia (low temperature). A temperature over 38Â°C (100.4Â°F) most often means you have a fever caused by infection or illness. It is generally medically accepted that normal body temperature ranges between 36.5Â°C (97.7Â°F) to 37.5Â°C (99.5Â°F).
Thermometers are used to measure the body temperature and can be calibrated in degrees Fahrenheit (Â°F) or degrees Celsius (Â°C) depending on the global region. The normal body temperature of 98.6Â°F (37Â°C) is actually an average of temperatures.A person's normal temperature can fluctuate 1Â°F (0.6Â°C) or more or below 98.6; additionally, the body temperature fluctuates the same amount throughout the day-lower in the morning and evening while higher at mid-day.he normal body temperature of 98.6Â°F (37Â°C) is actually an average of temperatures. A person's normal temperature can fluctuate 1Â°F (0.6Â°C) or more or below 98.6; additionally, the body temperature fluctuates the same amount throughout the day-lower in the morning and evening while higher at mid-day.