Magnetic Network
In the solar chromosphere, patches of magnetic activity (shown in black and white) concentrate in the periphery of roundish structures, which we call the magnetic network. The network is brighter than the cell interior: the image displays a map of the magnetic field and contours of enhanced Ly-α emission, which outline the magnetic network.
In the network, magnetic loops protrude from the solar interior and open into over-arching structures, while the cell interiors are filled with low-lying loops. Less self-reversed profiles cluster along the network boundary, here the expanding magnetic field forms funnel-like structures with reduced opacity.