DSCOVR, formerly called Triana, is the first Earth-observing satellite in an Lagrange-1 or L1 orbit.  It supports a number of scientific instruments, including EPIC and NISTAR.  EPIC (Earth Polychromatic Imaging Camera) is a 10-channel sepctroradiometer that provides daily 13 (in winter) or 22 (in summer) 10 narrow band spectral images of the entire sunlit face of Earth.  NISTAR is an instrument that measures the outgoing radiation from the Earth, and employs three electrical substitution radiometers and a photodiode to measure reflected sunlight and infrared emission.