A kind of aqueous ‘mud’ together with ‘antifreeze’ components such as ammonia or methane would have come out of the crater of these formations
It was the summer of 2015 when NASA’s New Horizons probe approached just 12,500 kilometers from the surface of Pluto, the closest human technology has ever come to that icy world. The images revealed two strange and huge mountains with craters on their crests that suggested they could be something like volcanoes. Named Wright Mons and Picard Mons, at that time they puzzled scientists, who now, with much more information and data in hand, have been able to discover that, indeed, Pluto’s landscape is sculpted by cryovolcanoes that would have a type and scale never before seen in the entire Solar System.
The conclusions have just been published in ‘ Nature Communications ‘.
Located on the heart-shaped plain of Sputnik Planitia, these formations reach 7,000 meters in altitude and between 10 and 150 kilometers in width. Since its discovery, the area has drawn a lot of attention from scientists, as such massive formations in a place with hardly any impact craters suggested that some kind of geological mechanism sculpted the terrain relatively recently. However, Pluto is almost 40 times the distance from the Earth to the Sun and, although it has a rocky core, it is believed that its temperature was relatively low during its entire formation, even more so at the end of its creation. Or so it was thought until now.
The researchers believe that at some point in the dwarf planet’s ‘recent’ history, not incandescent lava appeared in that area as it does here on Earth, but rather muddy water sludge emerging from these icy craters along with ‘antifreeze’ elements such as ammonia or methane. “Everything indicates that it was not liquid since the environment is too cold: the average temperature of Pluto’s surface is approximately 40 Kelvin (-233 C)”, explains Kelsi Singer, from the Southwest Research Institute and a researcher on the probe. New Horizons to ‘ The Guardian’. “It would probably be more of a muddy material, or it could even be mostly solid, like a glacier, but still minimally flowable.” When they emerge on the surface, in contact with the icy conditions of this world in the dark and remote zone of the Kuiper Belt, these ‘lava’ solidify, creating new slopes, especially in the upper part, near the ‘mouths’ of the volcanoes.
In addition, the team notes that there are not just two craters on Wright Mons and Picard Mons, but several smaller ones that have coalesced to form the unusual mountainous terrain, resembling a kind of solidified mud that does not occur anywhere else in the world. Solar system. And this is despite the fact that cryovolcanic activity has been discovered in recent years on the dwarf planet Ceres, on the moons Titan and Europa, even on a natural satellite of Pluto’s own, Charon. So massive, in fact, that researchers have compared the size of these cryovolcanoes by volume to the Hawaiian volcano Mauna Loa, one of the largest on Earth.
“The extrusion of icy material onto the surface of a body with extremely low temperatures, low atmospheric pressure, low gravity, and the abundance of volatile ices found on Pluto’s surface makes it unique among visited places in the Solar System,” the authors write.
Here the question is: how in really cold conditions can this process take place? According to the authors, it is only explained by the argument that Pluto may actually store heat better than previously thought. “Pluto’s structure and evolution allow for greater heat retention or more heat overall than was anticipated before New Horizons arrived,” the team states in their study, “because these temperatures allowed for the mobilization of carbon-rich materials.” water ice at some recent point in the history of dwarf planet formation.”
Even so, the mystery continues, since researchers still do not know what happened (or happens) under Pluto’s subsurface, in which nothing should flow, not even minimally. It seems that this dwarf planet is much more than just an icy ball on the edge of our cosmic neighborhood.
