The sun’s atmosphere dances. Giant columns of solar material — made of gas so hot that many of the electrons have been scorched off the atoms, turning it into a form of magnetized matter we call plasma — leap off the sun’s surface, jumping and twisting. Sometimes these prominences of solar material shoot off, escaping completely into space; other times they fall back down under their own weight. The prominences are sometimes also the inner structure of a larger formation, appearing from the side almost as the filament inside a large light bulb. The bright structure around and above that light bulb is called a streamer, and the inside “empty” area is called a coronal prominence cavity. Scientists have published new research on the temperatures of the sun’s coronal cavities. By understanding aspects of these cavities — that is the shape, density and temperature — scientists can better understand the space weather that can disrupt technologies near Earth.