This is one of the highest resolution photographs of a spicule on the Sun. There are thousands of these tubes of hot gas on the surface of the Sun. Their size is comparable to the width of a state and the length of the Earth. The surface of the Sun is always flowing and changing, due to the motion of "solar rivers" on and beneath the Sun's surface. The tubes are shaped by magnetic fields. They are difficult to study, due to their fast motion and short life. Surprisingly, the cause of these spicules is thought to be sound waves trapped in the Sun. They shoot out if they escape, but soon are quieted down and bounce around inside the Sun. The dark area in the lower right is a sunspot, where some of the spicules seem to be converging. The definite cause of these plasma jets is yet to be discovered.
