American Geophysical Union | 2020 Feb 04
A “beating heart” of frozen nitrogen controls Pluto’s winds and may give rise to features on its surface, according to a new study.
Pluto’s famous heart-shaped structure, named Tombaugh Regio, quickly became famous after NASA’s New Horizons mission captured footage of the dwarf planet in 2015 and revealed it isn’t the barren world scientists thought it was.
Now, new research shows Pluto’s renowned nitrogen heart rules its atmospheric circulation. Uncovering how Pluto’s atmosphere behaves provides scientists with another place to compare to our own planet. Such findings can pinpoint both similar and distinctive features between Earth and a dwarf planet billions of miles away.
Nitrogen gas – an element also found in air on Earth – comprises most of Pluto’s thin atmosphere, along with small amounts of carbon monoxide and the greenhouse gas methane. Frozen nitrogen also covers part of Pluto’s surface in the shape of a heart. During the day, a thin layer of this nitrogen ice warms and turns into vapor. At night, the vapor condenses and once again forms ice. Each sequence is like a heartbeat, pumping nitrogen winds around the dwarf planet.
New research ... suggests this cycle pushes Pluto’s atmosphere to circulate in the opposite direction of its spin – a unique phenomenon called retro-rotation. As air whips close to the surface, it transports heat, grains of ice and haze particles to create dark wind streaks and plains across the north and northwestern regions. ...
Pluto’s Beating Heart Regulates the Atmospheric Circulation: Results
from High Resolution and Multi-Year Numerical Climate Simulations ~ T. Bertrand et al