The Incredible Geology of Pluto

Astrogeology, Asteroids, Robots, Space Flight & Extraterrestrial Matters

Date posted: 02/18/16

Dana Hunter opines that when she was young, she should have realized that we would one day be doing geology at the ends of the solar system. If she had known then she could have combined her love of astronomy with her passion for geology, she might even have abandoned her dreams of fiction writing and poured herself into a degree in the planetary sciences. Now that we have robots in space doing remote geology on other worlds, we have seen what the rovers on Mars have been up to. We have now turned to distant Pluto, which recently got downgraded to dwarf planet status. But just because a world is small does not mean it cannot have world-class geology, and the things we are finding on Pluto are truly phenomenal. Hunter is intrigued! She wants to know what geologic processes are acting on Pluto that resurface the planet and erase the impact craters in some regions. She wants to know more about these pits, and the different kinds of ice that are basically rocks on this frigid, distant dwarf planet. And, she cannot wait for the technical papers to start coming out! Pluto has mountains and plains and glaciers, so much like Earth, only so very different. NASA scientists speculate that the mysterious indentations may form through a combination of ice fracturing and evaporation. The scarcity of overlying impact craters in this area also leads scientists to conclude that these pits, typically hundreds of yards across and tens of yards deep, formed recently. Their alignment provides clues about the ice flow and the exchange of nitrogen and other volatile materials between the surface and the atmosphere. We do not have enough information to do more but vaguely describe what we are seeing on Pluto, but it is a start. Human geologists may never be able to stand on the icy features of Pluto, but Hunter hopes that in our lifetimes, a robot will one day be able to explore, sample, and analyze those intriguing features and report back to geologists on Earth for meaning.