A global pattern in the Sun's chromosphere, formed by bright and dark mottles visible in Hα light or the calcium H and K lines. The network marks regions of strong magnetic field, and coincides with boundaries of the supergranulation on the photosphere below. Coarse bright mottles outline the network. Fine mottles, both dark and bright, are arranged in clusters, with their bases rooted in coarse mottles. These small mottles are probably spicules seen against the Sun's disk. The network extends into the transition region above the chromosphere, but fans out into the corona and can no longer be detected there.
Subjects: Astronomy and Astrophysics.