Which term describes a celestial body that gives off light?

The term "luminary" generally refers to an object that emits light or is a source of light. In the context of celestial bodies, it encompasses various types of luminous entities, including stars and planets that reflect light, but typically emphasizes those that inherently produce light.

In contrast, while "star" is another term that specifically describes celestial bodies that generate their own light through nuclear fusion, "luminary" is broader and can refer to both natural and artificial sources of light in various contexts. It reflects a wide understanding of light-emitting objects, including stars, moons, and man-made lights.

On the other hand, "planet" and "asteroid" describe celestial bodies that do not produce their own light. Planets reflect light from their nearby stars, while asteroids are small rocky bodies that mostly reflect light as well, having no intrinsic luminosity. Thus, labelling a celestial body that gives off light as a "luminary" is more encompassing and can position it within both astronomical and metaphorical contexts.