People in the UK were treated to a partial solar eclipse a few minutes . But several observers spotted some strange black dots on the sun . These were sunspots , caused by concentrations of magnetic fields . They are sometimes associated with eruptions such as solar flares . And they can be more than ten times as big as Earth .
People in the UK were treated to a partial solar eclipse this morning . But several observers spotted some strange black dots on the sun . These were sunspots , caused by concentrations of magnetic fields . They are sometimes associated with eruptions such as solar flares . And they can be more than ten times as big as Earth .