Astronauts' core body temperature is 1 degree C (almost 2 deg F) higher in space than on Earth. When exercising, some astronauts in space experience body temperatures as high as 40 deg C (104 deg F). Higher body temperatures negatively impact both cognitive and immune functioning.

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Astronauts' core body temperature is 1 degree C (almost 2 deg F) higher in space than on Earth. When exercising, some astronauts in space experience body temperatures as high as 40 deg C (104 deg F). Higher body temperatures negatively impact both cognitive and immune functioning.