Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI), is an instrument on the New Horizons space probe to Pluto and beyond, it is designed to measure ions and electrons.[1] Specifically, it is focused on measuring ions escaping from the atmosphere of Pluto during the 2015 flyby.[2] It is one of seven major scientific instruments aboard the spacecraft.[3]
PEPSSI is designed to help understand the rate of atmospheric loss from the atmopshere of Pluto into space, which is thought experience i comet-like atmosphere loss into outer space.[4][5]
See also
MAVEN (Mars orbiter that also focused on studying planetary atmospheric interaction with the solar system medium)
