The Winds of Pluto: Modeling the Atmosphere

Pluto no longer hangs out with the solar system’s cool kids, the planets, but astronomers studying this remote world continue to discover its surprising, planet-like dynamism.
Researchers have hacked simple climate-modeling algorithms for Mars to simulate the winds of Pluto’s fleeting atmosphere.

Pluto’s winds. Courtesy Angela Zalucha and Amanda Gulbis
The new computer simulations not only suggest the dwarf planet’s winds may exceed 225 miles per hour, but also that they whisk around the ice ball in a clockwise direction — right in step with Pluto’s rotation.
“It’s surprising that the winds are so fast. We think it has this weak little atmosphere, but apparently it can do a lot,” said Angela Zalucha, a planetary scientist at the Southwest Research Institute in Boulder, Colorado.
Zalucha and Amanda Gulbis, a planetary scientist at MIT, wrote a study about their new model of Pluto’s atmosphere published April 10 in the Journal of Geophysical Research.
It’s the first time anyone has attempted to model atmospheric circulation on the small, icy world. And while Pluto orbits the sun from about 3.7 billion miles away, the ever-improving model may eventually help scientists studying our home planet’s winds.
“We need to study all of the atmospheres we can get our hands on,” Zalucha said. “Successfully modeling simple atmospheres can help us understand more complex atmospheres, including the Earth’s.”
Mysterious Ice Ball
When budding astronomer Clyde Tombaugh in 1930 discovered Pluto, it was a tiny, moving speck in photographs taken weeks apart. Decades passed and we still knew comparatively little about the body.
Even as the Pioneer and Voyager spacecraft zoomed through the solar system in the 1970s, they missed Pluto in favor of studying Jupiter, Saturn, Neptune and Uranus, adding little to no knowledge about Pluto. During the spacecraft’s flights, however, a lone astronomer discovered Pluto’s moon Charon. The new object helped researchers narrow Pluto’s estimated mass to about one-sixth that of our moon.
It wasn’t until 1988 that astronomers discovered irrefutable signals of Pluto’s atmospheric veil. A team of researchers used a telescope to spy on Pluto as it passed in front of stars. The starlight passed through atmospheric gases, betraying their presence as they hugged the object’s -382-degree-Fahrenheit surface.
As telescopes improved, so did information about Pluto. Decades of distant observations, with the high-power help of the Hubble telescope and computer simulations, have even led astronomers to create fuzzy maps of the dwarf planet.