If an object gives off light, it is a luminous object.The luminous object gives off its energy and we see it. If you shine light on an object, it is an illuminated object, it just reflects the light back into your eyes.
If an object absorbs all the colors of light, it will appear to be black. It is the reflected part of the spectrum that gives an object its color.
An illuminated object reflects light that came from somewhere else. A luminous object emitts its own light.
Reflection
Yes, it is. Fireworks gives off its own light.
A star
Natural
Natural
Luminescent. If is a biological process, it is called bioluminescence.
because there is no light for it to reflect off
If an object gives off light, it is a luminous object.The luminous object gives off its energy and we see it. If you shine light on an object, it is an illuminated object, it just reflects the light back into your eyes.
The sun. All other objects reflect heat and light from the sun.
All objects warm enough to glow. It depends on what you count as 'light'. If you count all electromagnetic radiation, then all objects above absolute zero give off their own heat and light. Except, maybe, black holes. The answer for them is not so clear-cut.
It is a light source.
A luminous object can reflect light off other light sources. But it can also produce its own light.
A torch emits light from the bulb. A mirror gives off light by reflection.
The sun is capable of producing its own light.