On the icy, dotted gray surface of the dwarf planet Pluto, a peculiar snail-like object seems to be making its journey up north, reaching a tiny fork in the road.
This fascinating and strange visual was captured by NASA's Lorri or Long-Range Reconnaissance Imaging instrument aboard the New Horizons spacecraft during its July 14 flyby last year.
Lorri transmitted the high-resolution image back to Earth on Dec. 24, along with several other photos, showing the icy region with broken terrain known as Sputnik Planum where the mysterious object was spotted.
What Could This Snail-Like Object Be?
UFO and alien enthusiasts might say this strange image could prove the existence of extraterrestrial life on Pluto. It could very well be a creature trekking along Sputnik Planum, minding its own business.
However, NASA says that this idea is most unlikely.
The snail-like object is possibly a dirty block of ice "floating" on the solid nitrogen surface, which is denser than the object. Because of the difference in density, the icy object has been pulled to the edge of a "convection cell."
Convection cells are responsible for the blowing of wind on Earth. Usually, when a fluid is warmed, it loses its density and is forced into a region with greater density. For instance, macaroni can rise and sink in a boiling pot of water because of the phenomenon of convection cells.
On Sputnik Planum, scientists believe that Pluto's modest internal heat is causing the icy object to become buoyant or to float.
"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," says planetary scientist Dr. William McKinnon, the deputy lead of NASA's New Horizons Geology, Geophysics and Imaging team.
Sputnik Planum, The Left Side Of Pluto's "Icy Heart"
Sputnik Planum is a region lower than most of the places on Pluto's surface, but it is not completely flat, NASA says. It forms to the left side of the dwarf planet's "icy heart."
The icy region's surface is separated by polygons or cells 10 to 25 miles wide. When viewed at low sun angles, NASA says the cells seem to have ridged margins and slightly elevated centers, with about 100 yards of overall height differences.
NASA scientists say the odd pattern of the cells comes from the slow heat transfer taking place on Sputnik Planum's nitrogen surface, which is a reservoir that's possibly several miles deep.
The solid nitrogen surface is warmed by Pluto's internal heat, making it rise in great blobs, thus forming the snail-like icy object. The solid nitrogen then cools off and sinks again, renewing the convection cycle.
Meanwhile, scientists also believe that thousands of pits on the icy region's surface may form by sublimation, or the transformation of a solid substance directly to a gas phase.
The "X" Factor
Aside from the snail-like object and the tiny fork in the road, the image also revealed an "X" marked on the right side of the icy object.
Scientists from the New Horizon team ran computer models that showed these blobs of floating nitrogen objects can slowly evolve and merge over millions of years.
The ridged margins on Sputnik Planum's surface mark the location where the cooled nitrogen object sinks back down. These broken trails can also be nipped off and abandoned.
The "X" on the high-res image is possibly one of these abandoned ridged margins, a former quadruple junction where four convection cells used to meet on each tip of the "X." There are a lot of active triple junctions on the Sputnik Planum mosaic which Lorri sent to Earth.
Pluto's Viking Terra Area
NASA also showed a 160-mile long composite image of Pluto's Viking Terra Area.
Scientists are particularly interested in the bright methane ices condensed on the region's crater rims; the dark red tholins or small soot-like particles that are the result of methane and nitrogen in the dwarf planet's atmosphere; and the layers on steep cliffs and crater walls.
The thick red material may contain particles that ride along with the ice that flows underneath the surface or are being blown away by the dwarf planet's winds, experts say.
Both the photos of the Viking Terra Area and of Sputnik Planum are the latest high-res images that expose the pits on Pluto's "icy heart."
