There’s a weird, snakeskin-looking terrain found on Pluto, and scientists have found that it actually has a counterpart on Earth, a new study shows.
These “scales,” imaged by NASA’s New Horizons spacecraft during its July 2015 flyby, are icy ridges that are about 1,650 feet tall, forming a bladed terrain on Pluto's Tartarus Dorsa region. They are quite similar to Earth’s “penitentes,” which are bowl-shaped depressions featuring spires around their edge and emerge a few meters above the ground in its cold mountain regions due to erosion.
A team from York University in Toronto used computer simulations to model the penitente-like features on the dwarf planet. They tweaked factors such as temperature and windspeed to reflect the harsh surface conditions on Pluto.
“This gargantuan size is predicted by the same theory that explains the formation of these features on Earth,” said lead author John Moores in a statement, adding that they successfully matched the size and separation, ridges’ direction, and age of the icy ridges — three key pieces of evidence supporting their identification as penitentes.
Note, however, that these features of Pluto and Earth are different in size and composition: Pluto’s are much bigger at 500 meters (1,640 feet) tall and set apart by up to 3.1 miles (5 kilometers) versus our planet’s meter-sized versions. Pluto’s ridges are also made up mostly of methane and nitrogen ices, while Earth’s are composed of snow or water ice.
Pluto’s environment is much colder, its sun much dimmer, and its air much thinner than those of Earth.
While only Earth and Pluto are known today to have these icy ridges, the same features may also exist elsewhere in the solar system and in bodies outside of it given the right environmental conditions, such as having an atmosphere and low temperatures. An atmosphere is necessary, for instance, explaining why the ridges have not been found previously on other dwarf planets or icy satellites.
The findings are discussed in the journal Nature.
The freshly identified penitentes on Pluto are not its only surprising features discovered so far. The dwarf planet has also been found to have exotic icy mountains, a blue sky, and a surface that actively evolves. Speculations also point to the presence of an underground ocean.
Data download from New Horizons is already complete, but analysis is still ongoing. The spacecraft is on its way to a rendezvous with Kuiper Belt Object 2014 MU69 this 2019.
Pluto’s ice is a two-lobed formation on the surface, with the western one — called Sputnik Planitia — showing to be a deep basin that hosts carbon monoxide, methane, and frozen nitrogen. A new study last month suggested that the ice formed early in Pluto’s history and not because of an impact with an external object.
Researchers have also long wondered if Pluto, being a great ball of ice, could also be capable of hosting life. Another study published a month ago claims that it is possible for aquatic life forms to survive within its subsurface oceans.