Active Sun. SOHO image of solar activity, showing loops in the corona, the outer layer of the Sun. The temperature of the material here is around a million Kelvin. The loops are made visible as hot material is ejected from the surface of the Sun and channeled along magnetic field lines. This image was taken in the light of Iron XI/X ions, at a wavelength of 171 angstroms (17.1 nanometres), by the EIT (Extreme Ultraviolet Imaging Telescope) instrument on board the SOHO (Solar and Heliospheric Observatory) spacecraft.