What can observations tell us about coronal heating

摘要: The actual source of coronal heating is one the longest standing unsolved mysteries in all astrophysics, but it only recent years that observations have begun making significant contributions. Coronal loops, their structure and sub-structure, temperature density details, evolution with time, may hold key to solving this mystery. Because spatial resolution current observatories cannot resolve fundamental scale lengths, information about corona must be inferred from indirect observations. Loops unexpectedly high densities multi-thermal cross-field temperatures were not consistent results expected steady uniform models. hot ( T >5 MK) plasma component loops also a observation; new sounding rocket instrument called Marshall Grazing Incidence X-ray Spectrometer will specifically target observable. Finally, loop likely tangle magnetic strands. High Resolution Imager observed braids untwisting reconnecting, dispersing enough energy heat surrounding plasma. existence multi-thermal, cooling provides observational constraints viable models need explain.