NASA discovers that vast frozen plains lie in the center of Pluto’s ‘heart.’
NASA’s New Horizons spacecraft has discovered a vast icy plains that appears to be no more than 100 million years old in the most recent image of Pluto’s surface released on Friday. The region lies within the center of Pluto’s heart-shaped feature, informally known as “Tombaugh Regio” — meaning Tombaugh Region — after Clyde Tomaugh, who discovered Pluto in 1930.
“This terrain is not easy to explain,” Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging Team (GGI) said. “The discovery of vast, craterless, very young plains on Pluto exceeds all pre-flyby expectations.”
The region is thought to be no more than 100 million years old due to the lack of impact craters seen. Scientists say this could indicate that the region is still being formed by geological processes. Dark streaks a few miles long seen in the region, which appear to be aligned in the same direction, may have been produced by winds blowing across Pluto’s frozen surface scientists say.
The region has been informally named “Sputnik Planum” — meaning Sputnik Plain — after the Earth’s first artificial satellite. Sputnik Planum is located just north of the recently discovered ice mountains on Pluto’s surface. [Read more: New Horizons Discovers Ice Mountains On Pluto]
‘Sputnik Planum’ is a broken surface composed of irregularly-shaped polygonal segments, measuring roughly 12 miles wide, separated by what are thought to be troughs. Some troughs contain darker material within them, while others rise above the surrounding area. In other areas, the surface appears pitted, possibly formed through a process called sublimation, where ice transforms directly from a solid to a gas.
“Scientists have two working theories as to how these segments were formed. The irregular shapes may be the result of the contraction of surface materials, similar to what happens when mud dries,” NASA said in a press release. “Alternatively, they may be a product of convection, similar to wax rising in a lava lamp. On Pluto, convection would occur within a surface layer of frozen carbon monoxide, methane and nitrogen, driven by the scant warmth of Pluto’s interior.”
The image, revealed on Friday, was captured using New Horizons’ Long Range Reconnaissance Imager on July 14 at a distance of 48,000 miles from Pluto. The image was compressed in order to return the image to Earth in a timely fashion. New Horizons is storing the uncompressed version of the image in memory until mission scientists begin downloading the spacecraft’s flyby data in full starting later this year.