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.

How do scientists define heat in terms of atomic behavior?

• As the size of atoms

• As the speed of atomic movement

• As the color of atoms

• As the weight of atoms

What is temperature a measure of?

• The color of atoms

• The average kinetic energy of atoms

• The weight of atoms

• The number of atoms

Why is it difficult to measure temperature in space?

• Because space is a vacuum

• Because space is too bright

• Because space is too noisy

• Because space is too crowded

What does the cosmic microwave background radiation signify?

• The existence of aliens

• The end of the universe

• The presence of black holes

• The early stages of the universe

What is the temperature of the cosmic microwave background radiation?

• 300 Kelvin

• 2.7 Kelvin

• 100 Kelvin

• 0 Kelvin