Solar Smoke Rings

Abstract

Astronomy![Figure][1] CREDIT: S. HABBAL ET AL., THE ASTROPHYSICAL JOURNAL 719 , 2 (20 AUGUST 2010) © 2014 IOP PUBLISHING The Sun's corona is over a hundred times hotter than the photospheric surface we are most used to seeing, but it is also a trillion times more diffuse. Comparatively faint features within the corona are therefore difficult to discern without blocking the photosphere, either with specialized cameras or during total eclipses. Druckmuller et al. took advantage of several eclipses from 2001 to 2010 to image the corona in white light with a range of exposure times that sampled its high dynamic range. By applying a new high-pass filter to these images, the authors extended the limit of visible features by three orders of magnitude. The observed complex and time-variant structures reflect the dynamic interaction of the coronal plasma with the turbulent magnetic flux over the solar surface. Familiar bright rays and looping arches dominate the corona on the largest scales, but more subtle vortex rings are newly revealed closer to the limb, with twisted helices and bubbles slightly farther out. The size range of structures in this turbulent medium may result from instabilities recorded in various evolutionary stages, and this hypothesis encourages future time-series observations that monitor these features continuously. Astrophys. J. 10.1088/0004-637X/785/1/14 (2014). [1]: pending:yes