First Stellar Occultations Shed Additional Light on Pluto's Atmosphere

Explanation: New Horizons succeeded in observing the first occultations of Pluto's atmosphere by ultraviolet stars, an important goal of the mission's Pluto encounter. This illustration shows how New Horizons' Alice ultraviolet spectrometer instrument "watched" as two bright ultraviolet stars passed behind Pluto and its atmosphere. The light from each star dimmed as it moved through deeper layers of the atmosphere, absorbed by various gases and hazes.

Pluto

Image credit: NASA/JHUAPL/SwRI