Scientists have discovered the mystery behind Pluto’s giant ice blades.
Giant ice blades found on Pluto are evidence that the dwarf planet is geologically active and experiences climate change, a new study published in Icarus reports.
The formations — which measure as tall as the Eiffel Tower — sit on so-called “Bladed Terrain,” a landscape found only in high elevations areas of Pluto.
While little is known about the phenomena, researchers from NASA found that the spikes are made out of frozen methane. Not only that, but their unique shape also suggests they have been steadily shaped by different climate patterns.
“When we realized that bladed terrain consists of tall deposits of methane ice, we asked ourselves why it forms all of these ridges, as opposed to just being big blobs of ice on the ground,” said lead author Jeffrey Moore, a planetary scientist at NASA, in a statement. “It turns out that Pluto undergoes climate variation, and sometimes, when Pluto is a little warmer, the methane ice begins to basically ‘evaporate’ away.”
To get a better idea of the way the spikes form, the team in the study looked at some of the terrestrial ice blades found on Earth. Such formations, — known as penitentes — are made of water and are also only found at high elevations. However, they are much smaller than the spikes on Pluto, Newsweek reports.
Scientists believe penitentes form because tiny inconsistencies in the surface reflect sunlight and cause certain parts to melt faster than others. This process can only occur in places that get a lot of light, which is why the formations are only found in high, dry places.
Though the team is not sure if Pluto’s spikes form entirely through vaporization, the formations do suggest the dwarf planet was once cold enough to freeze methane. Then, the spikes began to shape as the world warmed up over time. That shift means that Pluto sees active climate change in a way similar to Earth.
Little is known about Pluto’s climate, but the new findings could help shed light on the dwarf planet and its atmosphere. Scientists will continue to analyze the gigantic spikes to see what other processes they can discover on the distant world.