Charon's rifts hint at ancient sea.
Pluto's largest moon, Charon, is busting at the seams, and an ancient subsurface ocean might be to blame.
Ridges and valleys more than 6 kilometers deep, seen during the July 14 flyby of the New Horizons spacecraft (SN: 12/26/15, p. 16), suggest that the moon swelled at some point in its past. The rifts could have been carved by a belowground ocean that froze and expanded, tearing apart the satellite's surface, NASA announced February 18.
Today, Charon is laden with water ice. But long ago, heat left over from the moon's formation and from the decay of radioactive elements could have melted some of the ice and sustained an underground ocean. As the moon cooled and the water froze, the ice would have expanded, creating the cracks.
One of these fractures is part of Serenity Chasma, the informal name for one of the longest series of chasms in the solar system. With a length of 1,800 kilometers, Serenity is about four times as long as the Grand Canyon.
Caption: Parts of Charon's surface, seen in this image from the New Horizons spacecraft, appear to have been pulled apart, possibly by the freezing and expanding of a subsurface ocean.
Please note: Illustration(s) are not available due to copyright restrictions.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||ATOM & COSMOS|
|Article Type:||Brief article|
|Date:||Apr 2, 2016|
|Previous Article:||Preparations under way for cancer 'moonshot' launch.|
|Next Article:||Mite-virus alliance targets bees.|