If “X-Files” are defined as data about weird and alien phenomena, NASA’s New Horizons mission to Pluto has X-Files galore. And this week, the mission’s science team shared an X-File with an actual X on it.
The timing of Thursday’s image release couldn’t be much better, coming just a couple of weeks before “The X-Files” (the TV show, that is) returns to Fox for a six-episode run. But this is no publicity stunt; rather, it illustrates how weird geology can get on a world that features glaciers of frozen nitrogen.
The semi-solid nitrogen in a region informally known as Sputnik Planum slowly burbles up and down, due to thermal convection. When blobs of nitrogen rise up and press against each other, patterns of lines mark the boundaries between the blobs. When the blobs subside, the lines disappear.
“This part of Pluto is acting like a lava lamp, if you can imagine a lava lamp as wide as, and even deeper than, the Hudson Bay,” William McKinnon, a researcher from Washington University in St. Louis who’s the deputy lead of the New Horizons geology, geophysics and imaging team, said in a NASA feature.
The results can be seen in a mosaic of Sputnik Planum imagery. The pictures were captured during New Horizons’ flyby last July and sent back to Earth on Christmas Eve. A detail from the mosaic shows an X shape floating all by itself. Scientists say the X marks a spot where four blobs, or “cells,” came together a long time ago. Eventually, the blobs smoothed out, and the boundaries between them faded away – except at the X-shaped nexus.
Another weird feature can be seen above the X: That dark squiggly is thought to be a block of dirty water ice, floating on top of the denser, cleaner nitrogen ice. The speckles that cover the picture are pits in the glacier, probably caused by nitrogen’s sublimation into gas.
So what’s Pluto’s “dirt” made of? The dwarf planet’s dark materials appear to include organic compounds known as tholins, which are formed when the sun’s ultraviolet radiation degrades hydrocarbons such as methane and ethane. A color composite image released on Thursday shows brownish deposits of tholins at the bottom of craters in a region informally known as Viking Terra. This view combines high-resolution black-and-white data from New Horizons’ LORRI camera with lower-resolution color data from the Ralph/MVIC imager.
“In areas where the reddish material is thickest and the surface appears smooth, the material seems to have flowed into some channels and craters,” NASA said. “Scientists say tholin deposits of that thickness aren’t usually mobile on large scales, suggesting that they might be riding along with ice flowing underneath, or being blown around by Pluto’s winds.”
Winds on Pluto? What could be weirder than that? Here’s what: This raw image shows strange circular artifacts of scattered sunlight, shining through layers of haze in Pluto’s thin atmosphere.
— Shannon Stirone (@shannonmstirone) January 8, 2016
— Alex Parker (@Alex_Parker) January 8, 2016
You can expect still more X-Files (and interplanetary lens flares) ahead: New Horizons’ principal investigator, Alan Stern of the Southwest Research Institute, estimates that only about a quarter of the gigabytes’ worth of the data collected in July has been received so far. The other three-quarters will be transmitted back to Earth over the next several months.