NASA's most recent images of Pluto reveals unusual pits on the surface of the dwarf planet.

The stunning new image was taken by the Long Range Reconnaissance Imager (LORRI) on NASA's New Horizons spacecraft, which has been observing Pluto.

"It seems that the more we see of Pluto, the more fascinating it gets. With its prominent heart-shaped feature, icy mountains, and "snakeskin" terrain, Pluto has already surprised New Horizons scientists with the variety and complexity of its surface features," NASA said in a statement.

The image shows an "enigmatic cellular pattern" on the left and clusters of small pits and troughs at the bottom of the image and the upper right. It was taken in a region informally known as Sputnik Planum, which is composed of volatile ices like solid nitrogen.

The scientists have theorized that the pits formed from the sublimation or evaporation of the ice, but the reason for their unusual shapes and alignments is not as clear. The researchers also noted there are no impact craters visible in the images, suggesting Sputnik Planum is relatively geologically youthful.

"Pluto is weird, in a good way," said Hal Weaver, New Horizons project scientist with Johns Hopkins Applied Physics Laboratory in Laurel, Maryland. "The pits, and the way they're aligned, provide clues about the ice flow and the exchange of volatiles between the surface and atmosphere, and the science team is working hard to understand what physical processes are at play here."