Spot on the Sun

Spot on the Sun

. This sunspot consists of a dark umbra inside a light, filamentary penumbra. It is about twice as large as the Earth, or about 24 million meters in diameter. Outside the penumbra the solar granulation is visible. This photograph was taken with exceptional angular resolution of 0.2 arc-seconds or 150 thousand meters at the Sun, using the National Solar Observatory’s Vacuum Tower Telescope at the Sacramento Peak Observatory. [Courtesy of Thomas R. Rimmele, Association of Universities for Research in Astronomy (AURA), National Optical Astronomy Observatories (NOAO), and the National Science Foundation (NSF).]

Copyright 2010, Professor Kenneth R. Lang, Tufts University