# # Program information file # PROGRAM_ID 2023B028 PROGRAM_TITLE Temporal Evolution of Pluto's Surface in Late Spring PROGRAM_INV1 Bryan Holler PROGRAM_INV2 Leslie Young PROGRAM_INV3 Will Grundy PROGRAM_INV4 Silvia Protopapa PROGRAM_INV5 PROGRAM_SCICAT Centaurs / TNOs / KBOs PROGRAM_ABSTRACT_BEG Pluto will reach northern hemisphere summer solstice in 2029, leading to the prospect of significant and detectable changes in surface composition in the present epoch. Pluto has been observed spectroscopically by IRTF and SpeX for over 20 years, providing an unprecedented time-baseline for studying the timescales on which Pluto's surface evolves. Continued observations of Pluto should reveal the onset of complete volatile loss from the northern polar regions in the years leading up to the summer solstice. We propose to observe Pluto's surface ices in the near infrared [0.7-2.5 um] with SpeX in SXD mode to complement observations by the New Horizons spacecraft and improve the characterization of the temporal evolution of Pluto's volatile ices [especially CH4 and N2]. PROGRAM_ABSTRACT_END