Infrared Ear Thermometers
Before infrared ear thermometers humans used measuring devices filled with a chemical called zinc, that reacts to the heat in your body and expands naturally in the device measuring your body heat in the process, but in zero gravity, chemicals do not behave the same as they do in gravity.
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To be able to measure accurate body temperatures, NASA scientist engineered infrared ear thermometers that within seconds give you the most precise body temp reading you can get, and even store it as data for studies.