NASA's New Horizons Spacecraft and the Atmospheres of Pluto and Charon

Abstract:

Pluto has an N₂-dominated atmosphere with trace amounts of CO and CH₄,
and an as-yet unmeasured surface pressure that is probably between 5
and 50 microbar. This atmosphere is dense enough for for global
circulation, atmospheric waves, photochemistry, and, perhaps, cloud or
haze formation. Because N₂, CO, and CH₄ are also frozen as ices on
Pluto's surface, the atmosphere has a profound effect on the surface
composition and geology as well. The New Horizons spacecraft will
study the atmosphere of Pluto and search for an atmosphere on Charon
with its UV spectrometer (via airglow and occultation), two plasma
instruments, and its visible imagers; additionally, the infrared
spectral imager will study the frozen volatile ices on the surface. I
will review the current work on Pluto and Charon's atmospheres, with a
focus on current puzzles and the observations we have planned for NASA's
New Horizons spacecraft in 2015.