| MadSci Network: Astronomy |
Heat energy is mostly stored and expressed in the form of kinetic energy, that is, the movement of particles. Since there are no (or at least, very few) particles in space to be moving, the energy cannot be transmitted. However, light energy or radiation can travel through a void. The light from the sun is what travels here, and it is converted into heat energy as it strike the atmosphere and the ground.
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