Scientists Watch as a Distant World's Atmosphere Shrinks and Thins

As dwarf planet Pluto moves along in its distant, high-obliquity 248-year orbit, its atmosphere is changing. That's because it's beginning to travel through colder, darker parts of the outer Solar System for the next 88 years. As a consequence, the mostly-nitrogen atmosphere is expected to grow gradually thinner and eventually freeze out over the coming decades. When that happens, the atmosphere will shrink.