What can we tell about astronomical objects from the light coming from them?

Answer:

Introduction:

The astronomical objects which are coming from light are usually referred as Spectrum or spectral lines. The spectrum which is nothing but the group of wavelengths.

It is a simply a graph or chart that shows the intensity of light being emitted over a range of energies. The spectroscopy is a different one which can be used in helping researchers or scientists to understand how an object like a black hole, neuron star, or active galaxy produces light. How fast it is moving and the nature of the elements composed in it.