It hasn't been smooth sailing for Pluto as the smallest, farthest, and most freezing dwarf planet in the entire solar system.
Not only was Pluto kicked out of the official list of planets in the solar system in 2006, but now scientists are adding "atmospheric collapse" to the threats that the galaxy's most famous dwarf planet is facing.
Pluto's Atmosphere Is Dissolving
A team of scientists have been tracking the seasonal changes to Pluto's surface pressure using ground-based stellar occultations, which occur when a cosmic object blocks the light coming to Earth from a more distant source. By analyzing the way the dwarf planet blocks light from stars much farther away, researchers can find out more details about Pluto's atmosphere.
Findings that will be published in the journal Astronomy & Astrophysics show that the atmosphere is likely to freeze and collapse in the near future.
"We were able to construct seasonal models of Pluto and how it responds to changes with the amount of sunlight it receives as it orbits the Sun," said Andrew Cole, an astronomer from the University of Tasmania.
Pluto is already known to be the coldest dwarf planet in the solar system, but he added that the team discovered it can get so cold during certain seasons that nitrogen freezes out of the atmosphere when Pluto is farthest from the sun at its northern hemisphere's winter.
"The atmospheric pressure has tripled over the past three decades, but as the dwarf planet orbits, our modeling showed that most of the atmosphere would condense out to almost nothing left," Cole continued. "What our predictions show is that by 2030 the atmosphere is going to frost out and vanish around the whole planet."
How Pluto's Atmospheric Collapse Will Happen
Pluto, with its tilted elongated orbit, takes 248 Earth years to orbit the sun. Since 1989, when the dwarf planet reached its closest distance to the sun, it has been steadily retreating and its temperatures dropping accordingly.
Previous observations revealed that Pluto's atmospheric pressure did not drop in response to its drop in temperature. Instead, the atmospheric pressure actually began to rise, much to the surprise of scientists.
The new research provides an answer why, explaining that Pluto may be getting farther from the sun, but the north pole is exposed to sunlight at this point of its orbit. This means that the nitrogen ice cap is turning back into gas.
New climate modelling of the dwarf planet's atmosphere expects things to change very soon, though. As Pluto moves farther and farther from the sun, the light gets weaker and becomes insufficient to warm the south pole.
Eventually, its atmosphere will collapse and freeze onto the surface.
If Pluto does indeed freeze over, it will appear much brighter to Earth with sunlight reflecting more intensely on the nitrogen frost. However, the dwarf planet's terrain will become hidden and buried underneath.
