Star*

The Sun is the closest star to Earth and hence provides a unique opportunity to study numerous stellar phenomena in detail unprecedented to other stars. One such phenomena, which is a longstanding mystery, is coronal heating of low mass stars. The solar corona contains plasma in excess of 1 MK at all times, strong concentrations of magnetic field called active regions contain plasma at least up to 3 MK, and large flares heat plasma above 10 MK. Detection of soft X-rays (sxr) from the Sun provide direct information on coronal plasma of temperatures in excess of ~1 MK. CubeSats are a low-cost alternative to rapidly fill astrophysical observation gaps, that large missions are currently missing. The twin Miniature X-ray Solar Spectrometer (MinXSS) CubeSats are the first solar science oriented CubeSat missions flown for the NASA Science Mission Directorate. The twin MinXSS have provided measurements from 0.8 -12 keV, with resolving power ~40 at 5.9 keV, at a nominal ~10 second time cadence and have proven to be consistent with numerous solar observations, proving the scientific capability of CubeSats.