Explanation:
The scientists used the term electromagnetic spectrum to describe the entire range of light that exists in the universe. From gamma rays to radio waves, most of the light present in the universe invisible to us.
The electromagnetic spectrum describes all the wavelengths of light. It explores an otherwise invisible universe, from an exploding stars to the dark nebulae.
The electromagnetic spectrum that consists of radio waves (used in commercial television and radios, radar, microwaves ), infrared radiation, visible light, gamma rays, x-rays and ultraviolet radiation rays. All the wavelengths and frequencies of the electromagnetic spectrum is used in spectroscopy.
The Kelvin Scale is used, so the answer is temperature :)
