Final answer:
The splitting of spectral lines in the Sun's spectrum typically refers to observations made in the visible light band, where astronomers analyze the dark Absorption lines called Fraunhofer lines to understand the Sun's composition.
Step-by-step explanation:
When observing the splitting of spectral lines in the Sun's spectrum, visible light is typically used. The visible spectrum of the Sun has dark lines, known as Fraunhofer lines, which are caused by the absorption of light at specific wavelengths by elements in the solar atmosphere. These lines are key signatures astronomers use to determine the composition of the Sun and other stars. The study of these lines is a part of the field of spectroscopy, which is instrumental in understanding the physical and chemical properties of astronomical objects.
The electromagnetic spectrum includes a range of wavelengths from radio to gamma rays, with visible light falling in between. The spectrum of solar radiation most intense in the visible region, with the intensity dropping off rapidly for shorter wavelength ultraviolet (UV) light, and more slowly for longer wavelengths infrared (IR) light. It is important to observe celestial bodies in different bands of the spectrum, as each band can reveal unique information about the body, such as the activity in the Sun's atmosphere, which can be observed in the ultraviolet band.