Spicules

Spicules

. Rows of dark spicules, or little spikes, are seen in the red hydrogen-alpha light of the solar chromosphere. A spicule is a short-lived (minutes) narrow jet of gas spurting our of the solar chromosphere at supersonic speeds to heights as great as 15 million meters. Spicules are a thousand times denser than the surrounding gas, so they are seen in absorption against the bright chromospheric background. They appear to cluster in “hedgerows” or “tufts”. [Courtesy of the National Solar Observatory (NSO), the National Optical Astronomy Observatories (NOAO), and the National Science Foundation (NSF).]

Copyright 2010, Professor Kenneth R. Lang, Tufts University