News Summary

• Pluto is beginning an 88-year march through colder, darker parts of the outer Solar System.
• As a consequence, the mostly-nitrogen atmosphere is expected to grow gradually thinner and eventually freeze out over the coming decades.
• Scientists led by Planetary Science Institute's Senior Scientist Amanda Sickafoose are using the light from distant stars to track that thinning process.
• They've reported that recent observations show Pluto's atmospheric pressure decreased by 16% between mid 2021 and July 2023.
• The exact physics of the atmosphere isn’t well understood, but it is tightly coupled with the properties of Pluto’s surface ices.