What Makes Space 'Cold?'

The video explains that heat is the speed of atom movement, while temperature is the average kinetic energy of these atoms. In space, a vacuum, temperature cannot be measured directly. When people refer to space as cold, they mean the cosmic microwave background radiation, a remnant of the Big Bang, with a temperature of 2.7 Kelvin. This radiation is evidence of the universe's origins. Although space is inhospitable, modern spacecraft are equipped with temperature control, ensuring astronauts' safety.

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