Subsurface ocean may have been the cause of Charon's fractured surface
Thanks to the treasuretrove of images and data collected by NASA's New Horizons spacecraft,mission scientists have formulated a theory on the geological processthat created the vast chasms that mar the surface of Pluto's largest moon, Charon.
The above image wascaptured by New Horizons' Long-Range Reconnaissance Imager (LORRI) ata distance of around 48,900 miles (78,700 km) from Charon. It covers an area 240 miles (386 km) in length by 110 miles(175 km) in width, while boasting a resolution of 1,290 ft (394 m)per pixel. The lower half of the right hand image is color-coded to depict the elevation of the terrain.
Prior to the arrival ofNew Horizons, planetary scientists could never have anticipated thatPluto and Charon could play host to such a diverse range ofgeological features. From the vast network of ravines that mark themoon's surface, it is clear that Charon has experienced a period oftumultuous upheaval.
New Horizons missionscientists have put forward a theory as to how these scars came toform. Charon's surface is composed predominantly of a layer ofwater ice. Early in the moon's life, heat from the planet's interior, aided by the decay ofradioactive elements, caused some of the ice to melt and trickle downdeeper into the moon where it formed a subsurface ocean.
At some point inCharon's history, the underground ocean froze, increasing in volumeand forcing the skin of the moon to crack open. This period ofgeological instability produced vast networks of fractures.
The largestconcentration of the chasms, which is focussed around Charon'sequatorial region, stretches an impressive 1,100 miles (1,800 km)and plunges to depths of 4.5 miles (7.5 km).