Space MIAD Practice Test

What provides power to spacecraft when solar energy is ineffective?

1. Nuclear Energy

2. Wind Energy

3. Batteries and fuel cells

4. Geothermal Energy

The correct answer is: Batteries and fuel cells

When solar energy is ineffective, especially in deep space environments where sunlight is limited, spacecraft rely on batteries and fuel cells for power. These systems store electrical energy that can be used when solar panels cannot generate sufficient power. Batteries can provide immediate power for onboard systems and experiments, while fuel cells can generate electricity through chemical reactions, often using resources like hydrogen and oxygen. This approach is crucial for the functionality of spacecraft during various mission phases, such as during the shadow of a planet or when the spacecraft is traveling far from the sun. Other energy sources, like nuclear, offer an alternative but are not widely used in all spacecraft due to complexity and safety concerns; wind and geothermal energy are not viable options in space. Thus, batteries and fuel cells are the most practical and reliable sources of energy to maintain operations when solar energy cannot be harnessed.