What is a characteristic of a star as opposed to planets and moons?

A defining characteristic of a star is its ability to produce its own light as a result of nuclear fusion occurring in its core. This process involves the conversion of hydrogen into helium, releasing an immense amount of energy in the form of light and heat, which is why stars shine brightly in the night sky. This fundamental property differentiates stars from planets and moons, which do not generate their own light but instead reflect the light from stars.

In contrast, planets are celestial bodies that orbit stars and can only be seen due to the light they reflect. Moons, which orbit planets, share a similar characteristic and also do not have the capability to create their own light. The other options provide misinformation about the nature of planets and moons, and they do not accurately describe the key attributes that make stars unique. Therefore, the statement about a star producing its own light due to nuclear reactions in its core is the correct answer and illustrates the essential difference between stars and other celestial bodies.