High resolution X-ray spectra of the sun

The last few years have seen great advances in the instrumentation used to obtain X-ray spectra of the Sun. These new observations reveal a wealth of multiplet structure containing many lines which allow us to understand more of the nature of the coronal plasma. Three areas of interest are examined. (1) The temperature sensitive satellite lines to helium-like resonance lines. (2) The strong lines of neon-like iron, Fe XVII. (3) The combination of high spectral and high spatial resolution (Skylab) observations. (author)