Pluto’s atmosphere may completely collapse and freeze by 2030, according to a 28-year study of the small, cold dwarf planet on the edge of our solar system.
Every 248 years, Pluto completes another orbit around the sun. This long orbit and its great distance from the star means the surface temperature is between minus 378 and minus 396 degrees Fahrenheit.
But Pluto, which has been subjected to the “planet or dwarf planet?” debate for years, is the most distant of its kind with an atmosphere in our solar system. The atmosphere is largely made up of nitrogen, with hints of carbon monoxide and methane.
An international collaboration of scientists from eight countries has been studying Pluto’s atmosphere and its evolution since 1988 using ground-based telescopes. These observations were compared with additional information gathered by the New Horizons spacecraft flyby of Pluto in 2015.
A study published in the journal Astronomy and Astrophysics recently shares data on Pluto’s atmosphere gathered between 1988 and 2016.
The data was used to model seasons on Pluto and how those react to the amount of sunlight it receives during different parts of its orbit. The researchers were able to record how surface pressure evolves during the seasons on Pluto.
This helped paint a complete picture of the atmosphere, including density, pressure and temperature.
“What the study found was when Pluto is farthest away from the Sun, and during its Winter in the Northern Hemisphere, nitrogen freezes out of the atmosphere,” said Andrew Cole, study author and associate professor at the University of Tasmania’s School of Natural Sciences, in a statement.
“The atmospheric pressure has tripled over the past three decades, but as the planet orbits, our modelling showed that most of the atmosphere would condense out to almost nothing left,” he said. “What our predictions show is that by 2030 the atmosphere is going to frost out and vanish around the whole planet.”
The data was gathered when the researchers were able to observe ground-based stellar occultations, when planets pass in front of background stars. This allows scientists to measure how much starlight is absorbed by a planet’s atmosphere.
These observations are tricky. The telescopes have to be positioned in the right spot to capture when a path outlined by the planet’s shadow also passes over a spot on Earth. This lasts only a minute or two.
If Pluto’s atmosphere collapses and freezes over, the dwarf planet may appear brighter in our sky because it will reflect more sunlight, Cole said.
“The striking red terrain seen in the New Horizons images could fade away if they are snowed under with nitrogen frost,” he said. “This research has been crucial in furthering our understanding of Pluto and testing what we know about atmospheres, ices, and climate at extreme conditions.”
