Ralph: Visible and infrared imager/spectrometer; provides color, composition and thermal maps.
Alice: Ultraviolet imaging spectrometer; analyzes composition and structure of Pluto's atmosphere and looks for atmospheres around Charon and Kuiper Belt objects (KBOs).
REX: Measures atmospheric composition and temperature; passive radiometer.
LORRI: telescopic camera; obtains encounter data at long distances, maps Pluto's far side and provides high-resolution geologic data.
SWAP: Solar wind and plasma spectrometer; measures atmospheric "escape rate" and observes Pluto's interaction with solar wind.
PEPSSI: Energetic particle spectrometer; measures the composition and density of plasma (ions) escaping from Pluto's atmosphere.
SDC: Built and operated by students; measures the space dust peppering New Horizons during its voyage across the solar system.