pluto snakeskin
In this extended color image of Pluto taken by NASA’s New Horizons spacecraft, rounded and bizarrely textured mountains, informally named the Tartarus Dorsa, rise up along Pluto’s day-night terminator and show intricate but puzzling patterns of blue-gray ridges and reddish material in between. This view, roughly 330 miles (530 kilometers) across, combines blue, red and infrared images taken by the Ralph/Multispectral Visual Imaging Camera (MVIC) on July 14, 2015, and resolves details and colors on scales as small as 0.8 miles (1.3 kilometers). NASA/JHUAPL/SWRI

Diverse, dazzling and mystifying. These are just some of the words that have been used over the past few weeks by space nerds as they pore over high-resolution photographs of the dwarf planet Pluto. With the latest batch of images, released by NASA Thursday, a few more adjectives are now being added -- “unique” and “perplexing.”

The new “extended color” images captured by the New Horizons spacecraft on July 14 -- which show Pluto’s surface across a range of spectra, some of which would be imperceptible to the human eye -- contain one showing “snakeskin” like surface features.

“It looks more like tree bark or dragon scales than geology,” William McKinnon, New Horizons Geology, Geophysics and Imaging (GGI) team deputy lead from Washington University in St. Louis, said in a statement Thursday. “This’ll really take time to figure out; maybe it’s some combination of internal tectonic forces and ice sublimation driven by Pluto’s faint sunlight.”

Abiding by the International Astronomical Union-approved theme for naming features on Pluto after our darkest imaginings, the bizarrely textured mountains are informally being called the Tartarus Dorsa. In Greek mythology, Tartarus is the name of a region of the underworld where the greatest sinners are sent for their transgressions.

Pluto already has a dark region called Cthulhu Regio -- named after H.P. Lovecraft’s Pacific-dwelling beast -- while its moon Charon has an area informally named after the realm of Mordor -- the residence of the dark lord Sauron in “The Lord of The Rings.”

High-resolution images of Pluto taken by NASA’s New Horizons spacecraft just before closest approach on July 14, 2015, reveal features as small as 270 yards (250 meters) across, from craters to faulted mountain blocks, to the textured surface of the vast basin informally called Sputnik Planum. Enhanced color has been added from the global color image. This image is about 330 miles (530 kilometers) across. NASA/JHUAPL/SWRI

“We used MVIC’s [Multispectral Visual Imaging Camera] infrared channel to extend our spectral view of Pluto,” John Spencer, a GGI deputy lead from Southwest Research Institute (SwRI) in Boulder, Colorado, said in the statement. “Pluto’s surface colors were enhanced in this view to reveal subtle details in a rainbow of pale blues, yellows, oranges, and deep reds. Many landforms have their own distinct colors, telling a wonderfully complex geological and climatological story that we have only just begun to decode.”

High-resolution images of Pluto taken by NASA’s New Horizons spacecraft just before closest approach on July 14, 2015, are the sharpest images to date of Pluto’s varied terrain—revealing details down to scales of 270 meters. In this 75-mile (120-kilometer) section of the taken from the larger, high-resolution mosaic above, the textured surface of the plain surrounds two isolated ice mountains. NASA/JHUAPL/SWRI

Additionally, the space agency also released a map of methane ice across parts of Pluto’s surface, revealing what the scientists called a "classic chicken-or-egg problem."

Higher concentrations of methane have been observed on bright plains and crater rims, and none have been seen in the centers of craters or darker regions. Outside Sputnik Planum -- a vast basin -- methane ice appears to favor brighter areas, but scientists aren’t sure if that’s because methane is more likely to condense there or that its condensation brightens those regions.

The Ralph/LEISA infrared spectrometer on NASA’s New Horizons spacecraft mapped compositions across Pluto’s surface as it flew by on July 14. On the left, a map of methane ice abundance shows striking regional differences, with stronger methane absorption indicated by the brighter purple colors here, and lower abundances shown in black. Data have only been received so far for the left half of Pluto’s disk. At right, the methane map is merged with higher-resolution images from the spacecraft’s Long Range Reconnaissance Imager (LORRI). NASA/JHUAPL/SWRI

“We’re unsure why this is so, but the cool thing is that New Horizons has the ability to make exquisite compositional maps across the surface of Pluto, and that’ll be crucial to resolving how enigmatic Pluto works,” Will Grundy, New Horizons surface composition team lead from Lowell Observatory in Flagstaff, Arizona, said in the statement.