Question

This photo shows the visible light spectrum of the Sun. Why does it have all those dark lines on it?

A) The dark lines are caused by Doppler shifts.
B) The dark lines are not real, but rather are artifacts of the photographic process used to record the spectrum.
C) The dark lines come from sunspots on the Sun, which are dark in color.
D) The dark lines represent wavelengths of light at which atoms near the Sun's surface absorb radiation from the hotter solar interior.

Answer 1

The dark lines in the Sun's visible light spectrum are caused by atoms in the Sun's surface absorbing light at certain wavelengths, which is then reemitted in other directions. These lines, called Fraunhofer lines, help astronomers analyze the chemical composition of the Sun and other stars.

Step-by-step explanation:

The dark lines in the visible light spectrum of the Sun, often referred to as Fraunhofer lines, are evidence of absorption by various chemical elements in the solar atmosphere. The atoms at the Sun's surface absorb light at certain wavelengths, and these result in dark lines in the spectrum because the absorbed light is reemitted in directions away from the observer. This absorption occurs in the cooler gas that makes up the Sun's outer atmosphere. The lines are specific to different elements and allow astronomers to determine the Sun's composition as well as study the composition and rotation of other stars. While the Doppler shift can also affect spectral lines, it is related to the movement of a star toward or away from us rather than the creation of dark lines in a static spectrum.