A body loses internal energy by emitting thermal radiation faster than it absorbs radiation or receives other heating. In a gravitating gas this can remove pressure support and allow further contraction.
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Radiative cooling is a natural process by which an object loses heat by emitting infrared radiation. This occurs when the surface of the object absorbs heat from its surroundings or the sun and then emits that energy in the form of thermal radiation. The efficiency of radiative cooling depends on several factors, including the temperature of the object, the ambient temperature, and the object's ability to emit infrared radiation.