Pluto image reveals strange slug-like object

ST. LOUIS, Jan. 11 (UPI) -- NASA continues to receive new data from its New Horizons probe. The data -- imagery and measurements collected by the craft's cameras and instruments -- continues to provide new and surprising details about Pluto's varied surface.

The latest surprise is a photo downloaded by NASA scientists late last year. The image offers an intimate view of the dwarf planet's icy plain called the Sputnik Planum.

An exposed rock on the dimpled, icy plain recalls a giant slug. The outcropping or lone chunk of debris lies along a demarcation line between different portions of the plain. The line resembles the trail of slime left behind by a slug or snail on the move.

But the line isn't slime; it marks a unique but subtle pattern on the plain. Zoom out and viewers will see Sputnik Planum divided by a series of lines. The icy plain looks like a collection of cells or tectonic plates.

Researchers say the differentiation is created by a deep-lying heat source. As large regions are gradually warmed, they bulge very slightly before cooling and sinking back. The slow warming and cooling routine creates a cell-like convection pattern.

"This part of Pluto is acting like a lava lamp," William McKinnon, a scientist at Washington University in St. Louis and head of geological imaging for the New Horizons mission, said in a press release. "If you can imagine a lava lamp as wide as, and even deeper than, the Hudson Bay."