Final answer:
An arching column of gas over a sunspot group is called a solar prominence, associated with the sun's magnetic field. These prominences and sunspots are key elements in the study of solar physics.
Step-by-step explanation:
An arching column of gas suspended over a sunspot group on the sun is referred to as a solar prominence. Solar prominences are large scale structures that are driven by the solar magnetic field. These structures are visible as bright arches when viewed from Earth. They are mostly composed of light, hot gasses held in place by the sun's magnetic field. The sunspot group is an area on the sun's surface that is literally cooler and darker than surrounding areas, and this tends to be where solar prominences often originate from. Overall, solar prominences and sunspots are fascinating aspects of solar physics.
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