Pluto’s thinning sky hints at nitrogen frost as it drifts from the Sun

A 2026 study of ten occultations (2017–2023) finds Pluto’s atmospheric pressure likely dropped about 16% since 2021, with nitrogen possibly freezing onto the surface as the dwarf planet moves away from the Sun. Model differences mean the future of Pluto’s atmosphere is not settled—some scenarios suggest further loss, others suggest a persistent, seasonally cycling atmosphere—making ongoing occultations crucial to map its long-term nitrogen cycle.