Close-up view Pluto’s moon Charon’s canyons taken by New Horizons. Multiple view photos allow stereo measurements of topography shown in the color-coded version of the image. The scale bar indicates relative elevation. Photo: NASA.
Pluto’s moon Charon is covered with ridges, scarps, and valleys caused by tectonic plates moving away from each other. It’s the opposite of how mountains are formed. But what formed the chasms on planet’s surface?
Serenity Chasm is part of an equatorial belt of chasms on Charon. It measures about 1,100 miles long and is up to 4.5 miles deep at it’s lowest point. The Grand Canyon is only 277 miles long and one mile deep.
Those giant chasms on the planet might have an explanation now. Thanks to evidence gathered by NASA’s New Horizons mission in July 2015, scientists think that the water on Charon, which is all frozen, may have been at least partially liquid at some point.
Researchers suggest that combined effect of decaying radioactive material and the moon’s internal heat, created during formation, that there is likely a subsurface ocean of liquid water.
As the moon cooled that ocean froze and the expanded. The expansion was so powerful that it pulled apart the surface of the moon in some areas. It’s a process similar to earth’s tectonic plates being pushed apart by the ocean.
Movement at this scale takes an immense amount of force, so the ocean must have been huge. The expanding water would have also pushed the plates up, effectively making the moon increase in size as well as becoming craggy.
The data reminds us that the universe is full of diversity. Charon, a body within our own solar system, has geology quite unlike our own.
On Earth, our tectonic plates float atop magma, which allows them to move by tiny amounts over a long period of time. Mountains are formed by them smashing together, as are continents sometimes. But Charon had a totally different mechanism that resulted in the plates moving.
