Astronomy Answers: From the Astronomical Dictionary

# Astronomy AnswersFrom the Astronomical Dictionary

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The description of the word you requested from the astronomical dictionary is given below.

the energy transport

energeia = [Greek] ability to do work; trans- = [Latin] over, portare = [Latin] carry

Energy transport can be done in three ways:

1. by convection (motion of a material), in which temperature differences make hotter material move to colder areas and colder material to hotter areas, which means that there is net heat (and so energy) transport from hot to cold areas.
2. by conduction (transport through a material), in which heat travels through a material without making the material itself move.
3. by radiation, in which energy travels through empty space (for example, as electromagnetic radiation such as light).

All three kinds of energy transport happen when you heat a pan of soup on a fire. The hot gases from the fire go up because of convection. The fire produces heat radiation, which you can block with your hand. The outside bottom of the pan is heated and conduction makes the heat reach the inside bottom of the pan, where it heats the soup. At first, the heat travels up the soup only by conduction, but later (when the soup is boiling) also by conduction.