Question

I agree that black holes are classified under non-luminous but to be a non-luminous object it must at least reflect light from another source BLACK HOLE don't reflect light but absorbs it, the reason why they're called back hole So how can they be classified as non-luminous?

Answer 1

Non -Luminous objects are those which do not have there own light but they reflect it from some other source.Black hole are also classified under this category because falling accelerated objects are the source of Light in it.When there is a fall of any object in Black hole then it becomes accelerated and gets high Temperature so there is a production of Thermal radiations.