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Why can energy from the Sun reach Earth through space?
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heat
What's the relationship between heat and temperature?
Energy from the Sun reaches Earth through space because it travels as thermal radiation. Unlike conduction or convection, which require a material medium to transfer heat, thermal radiation consists of electromagnetic radiation that can propagate through a vacuum at the speed of light.12
This process does not require an intervening medium to carry the energy from the Sun to Earth. The radiant energy emitted by the Sun is a result of nuclear fusion occurring in its core, where hydrogen atoms are converted into helium, releasing energy in the form of gamma-ray photons and kinetic energy. This energy eventually escapes the Sun's surface and travels across the vacuum of space to be absorbed by Earth.31