The geology of Pluto consists of the characteristics of the surface, crust, and interior of Pluto. Because Pluto is very far from Earth, studying it from our planet is very challenging. Many important details about Pluto were unknown until 14 July 2015, when the spacecraft New Horizons flew by Pluto and began sending data back to Earth. This mission showed that Pluto has a diverse and active geology, with features similar to those found on Mars.
After its flyby, New Horizons continued to send information home, with the last data arriving on 25 October 2016. These images and measurements showed that Pluto’s surface includes mountains, plains, and possible evidence of past volcanic activity. In June 2020, scientists announced that Pluto might have had a warm layer of water deep beneath its surface when it first formed. This raised questions about whether Pluto could have supported life in the very distant past.
Surface
See also: Geography of Pluto
Pluto's surface is mostly made of solid nitrogen, with small amounts of methane and carbon monoxide. The side of Pluto that faces its moon, Charon, has more solid methane. The opposite side has more nitrogen and carbon monoxide. The surface changes with seasons and is influenced by sunlight and landscape features.
Images from the Hubble Space Telescope and the New Horizons spacecraft show that Pluto's surface has many different colors and brightness levels. Some areas are dark and ancient, while others, like the bright and flat Sputnik Planitia, are much younger. The surface includes mountains made of water ice, plains filled with flowing nitrogen ice, and many craters.
Internal structure
Pluto's density is 1.87 g/cm3. Scientists think Pluto's inside has a rocky core with a mantle of water ice around it. The core may be about 1700 km wide, which is 70% of Pluto's total width.
The New Horizons spacecraft found that Pluto's inside might still be growing. This could be because of a deep ocean layer of liquid water. This is the first strong sign that Pluto has liquid inside. Pluto also does not have a magnetic field.
Images
This article is a child-friendly adaptation of the Wikipedia article on Geology of Pluto, available under CC BY-SA 4.0.
Images from Wikimedia Commons. Tap any image to view credits and license.
Safekipedia