Pluto's Mountains Are Snow-Capped, But The Serene White is Not Made Of Ice

The dwarf-planet of our solar system might give a tough competition to the serene Alps or even the majestic Himalayas. The images captured by NASA's New Horizons spacecraft in 2015 showed the Cthulhu range of the planet whose mountains even ascended to almost half the height of Mount Everest.

But here’s the catch, the frozen peaks of Pluto’s Cthulhu are not made of snow but frozen methane-rich ice.

A study published on Tuesday by science journal Nature has looked into the origin and cause of mechanisms driving the formation of Methane in the planet, especially the methane ice at the Cthulhu.

The researchers used high-resolution numerical simulations of Pluto’s climate to see that the processes forming the methane-ice are likely to be completely different to those forming high-altitude snow packed mountains on Earth.

Researchers found that the methane deposits may not result from adiabatic cooling in upwardly moving air like on earth, but from a circulation-induced enrichment of gaseous methane a few kilometres above Pluto’s plains that favours methane condensation at mountain peaks.

Whereas on Earth, the winds drive moist air upwards where cold temperatures cause water to condense and form snow which then covers the mountaintops. This discovery points out at the difference between atmospheric conditions of the two planets.

Given the vast distance between Sun and Pluto, the planet’s atmosphere is much thinner, almost on the verge of collapsing. Therefore, temperature at Pluto increases as one moves upward in the atmosphere.

At day time, most of the frozen methane in the region sublimates, turning from solid to gas. But at higher altitudes of Cthulhu’s peaks, the frozen methane remains which allows it to slowly build up over time.

The researchers used a numerical climate model of Pluto to investigate the origin of the methane-ice formation. Their simulations reproduced the accumulation of high-altitude methane ice where the frost-capped mountains are observed.

These were found particularly on the ridges and crests of the Pigafetta and Elcano Montes in eastern Cthulhu. The study proves that methane condensation is favoured by sublimation-induced circulation cells that seasonally enrich the atmosphere with gaseous methane at those higher altitudes.