The Kiladze Crater, a 27-mile wide structure situated in Sputnik Planitia, a heart-shaped region on Pluto’s surface, is thought to be a powerful cryovolcano, according to a new research paper on the pre-print server arXiv.

Cryovolcanoes are similar to the regular volcanoes found on Earth, but instead of spewing lava, they spurt out frozen water and other chemicals such as ammonia from within a celestial body.

The arXiv, which is yet to be formally peer-reviewed, suggests that the Kiladze crater is actually a cryovolcano due to observations of its appearance made by the New Horizons probe during its Pluto flyby in 2015.

"The tip-off that Kiladze is different from nearly all of the rest of the half of Pluto’s surface we explored with New Horizons in 2015, is the strong spectral signature of water ice.

Pluto, which orbits the sun at an average distance of 3.7 billion miles, is intensely cold and small, with a diameter of only around two-thirds the size of Earth’s moon.

"Even a centimeter of two of this organic smog would mask the water ice spectral signature we observe, and from this fact, we estimate that the age of Kiladze and surroundings (since the last eruption) is only a few million years.

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