The Coronal Veil

Coronal loops, seen in solar coronal images, are believed to represent emission from magnetic flux tubes with compact cross-sections. We examine the 3D structure of plasma above an active region a radiative magnetohydrodynamic simulation locate volume counterparts for loops. In many cases, loop cannot be linked individual thin strand volume. While loops present synthetic bright structures fewer, and complex shape. demonstrate that this complexity can form impressions even absence strands. difficulty discerning observations whether particular corresponds volume, or projection artifact. how apparently isolated could deceive observers, when multiple viewing angles available. we base our analysis on simulation, main findings independent setup illustrate intrinsic involved interpreting resulting line-of-sight integration optically plasma. propose alternative interpretation strands EUV images corona. The "coronal veil" hypothesis is mathematically more generic, naturally explains properties difficult address otherwise -- such as their constant cross section anomalously high density scale height. challenge paradigm tubes, offering new understanding corona and, by extension, other magnetically confined bright, hot plasmas.