Question

Define heat. What are its sources

Answer 1

Answer:

heat source is anything that can heat up a spacecraft. Heat sources can be external (from outside the spacecraft) or internal (from inside the spacecraft). External heat sources include: the Sun. reflected sunlight from planets and moons.

Answer 2

Answer:

Heating Energy Sources. Most radiant heating systems operate using warm water. It is not very hard to heat water. Here are only some of your many choices for heating energy sources: natural gas, propane (LP), oil, coal, wood, electricity, heat pumps, ground source heat pumps and solar energy.