How can we measure the strength of magnetic fields on the Sun?
A) By looking for the splitting of spectral lines in the Sun's spectrum
B) By observing the sizes of sunspots: Bigger sunspots mean a stronger field
C) By observing auroras here on Earth
D) Only by using sophisticated computer models because there are no observational ways of measuring magnetic field strength

Question

Quizplus · Accepted Answer

Spectral lines in the Sun's spectrum can be split due to the presence of a magnetic field, and the degree of splitting can be used to measure the strength of the field. This phenomenon is known as the Zeeman effect, and it is a commonly used method for measuring magnetic fields on the Sun and other stars. Option B is partially correct, as larger sunspots do indicate the presence of strong magnetic fields, but they don't necessarily give an accurate measure of the field strength. Option C is not relevant to measuring magnetic fields on the Sun, as auroras are caused by charged particles from the solar wind interacting with the Earth's magnetic field. Option D is not accurate, as there are observational methods available for measuring magnetic fields on the Sun.

How Can We Measure the Strength of Magnetic Fields on the Sun