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Why Is Pluto Losing its Atmosphere?
Scientists have detected a 16% drop in atmospheric pressure, possibly marking the beginning of a long-term decline.
Pluto, a dwarf planet discovered in 1930 at the edge of the Solar System, may be getting thinner or thicker as it moves away from and then closer to our host star in cycles lasting more than two Earth centuries.
New observations suggest that the thin layer of gas surrounding the planet has started to shrink as Pluto moves farther from the Sun, according to researchers at the Planetary Science Institute in Tucson, Arizona. Its atmospheric pressure fell by about 16% between 2021 and 2023.
Why does Pluto move away from the Sun now?
It takes Pluto about 248 Earth years to orbit the Sun. Its path is oval-shaped, so its distance from the Sun changes considerably. It reached its closest point in 1989 and will reach its farthest point in 2113 before moving closer again.
As Pluto moves away, it receives less sunlight. This can cool its surface and cause some of the frozen nitrogen to remain ice instead of turning into gas. As a…
