Pluto's 'Hulk-like' moon Charon: A possible ancient ocean?

February 19, 2016
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Pluto's largest moon may have gotten too big for its own skin.

Images from NASA's New Horizons mission suggest that Charon once had a that has long since frozen and expanded, pushing out on the moon's surface and causing it to stretch and fracture on a .

The side of Charon viewed by the passing New Horizons spacecraft in July 2015 is characterized by a system of "pull apart" tectonic faults, which are expressed as ridges, scarps and valleys—the latter sometimes reaching more than 4 miles (6.5 kilometers) deep. Charon's tectonic landscape shows that, somehow, the moon expanded in its past, and –like Bruce Banner tearing his shirt as he becomes the Incredible Hulk – Charon's surface fractured as it stretched.

Charon's outer layer is primarily . When the moon was young this layer was warmed by the decay of radioactive elements, as well as Charon's own internal heat of formation. Scientists say Charon could have been warm enough to cause the water ice to melt deep down, creating a subsurface ocean. But as Charon cooled over time, this ocean would have frozen and expanded (as happens when water freezes), pushing the surface outward and producing the massive chasms we see today.

This image focuses on a section of the feature informally named Serenity Chasma, part of a vast equatorial belt of chasms on Charon. In fact, this system of chasms is one of the longest seen anywhere in the solar system, running at least 1,100 miles (about 1,800 kilometers) long and reaching 4.5 miles (7.5 kilometers) deep. By comparison, the Grand Canyon is 277 miles (446 kilometers) long and just over a mile (1.6 kilometers) deep.

The lower portion of the image shows color-coded topography of the same scene. Measurements of the shape of this feature tell scientists that Charon's water-ice layer may have been at least partially liquid in its early history, and has since refrozen.

This image was obtained by the Long-Range Reconnaissance Imager (LORRI) on New Horizons. North is up; illumination is from the top-left of the image. The image resolution is about 1,290 feet (394 meters) per pixel. The image measures 240 miles (386 kilometers) long and 110 miles (175 kilometers) wide. It was obtained at a range of approximately 48,900 miles (78,700 kilometers) from Charon, about an hour and 40 minutes before New Horizons' closest approach to Charon on July 14, 2015.

Explore further: Mysterious mountain revealed in first close-up of Pluto's moon Charon

Related Stories

NASA image: Pluto's Wright Mons in color

January 15, 2016

Scientists with NASA's New Horizons mission have assembled this highest-resolution color view of one of two potential cryovolcanoes spotted on the surface of Pluto by the New Horizons spacecraft in July 2015.

NASA images: A day on Pluto, a day on Charon

November 20, 2015

Pluto's day is 6.4 Earth days long. The images were taken by the Long Range Reconnaissance Imager (LORRI) and the Ralph/Multispectral Visible Imaging Camera as the distance between New Horizons and Pluto decreased from 5 ...

Image: The youngest crater on Charon?

October 30, 2015

New Horizons scientists have discovered a striking contrast between one of the fresh craters on Pluto's largest moon Charon and a neighboring crater dotting the moon's Pluto-facing hemisphere.

Recommended for you

Freeze-dried food and 1 bathroom: 6 simulate Mars in dome

January 20, 2017

Crammed into a dome with one bathroom, six scientists will spend eight months munching on mostly freeze-dried foods—with a rare treat of Spam—and have only their small sleeping quarters to retreat to for solace.

Image: Wavemaker moon Daphnis

January 20, 2017

The wavemaker moon, Daphnis, is featured in this view, taken as NASA's Cassini spacecraft made one of its ring-grazing passes over the outer edges of Saturn's rings on Jan. 16, 2017. This is the closest view of the small ...

Video: A colorful 'landing' on Pluto

January 20, 2017

What would it be like to actually land on Pluto? This movie was made from more than 100 images taken by NASA's New Horizons spacecraft over six weeks of approach and close flyby in the summer of 2015. The video offers a trip ...

The evolution of massive galaxy clusters

January 20, 2017

Galaxy clusters have long been recognized as important laboratories for the study of galaxy formation and evolution. The advent of the new generation of millimeter and submillimeter wave survey telescopes, like the South ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

wduckss
not rated yet Feb 20, 2016
Where did this now? This is reset at the time of the ancient Greeks. Studies have (with zigzag) walked in the right direction and a thorough understanding of the matter. This is an evil intention or is written out of desperation.
Urgent return the effects of a binary system and elements and compounds of low melting point. Water ice search 0 ° C, at temperatures of -210 ° C as ice Fe tough and is not a working compound.
antialias_physorg
4.8 / 5 (4) Feb 20, 2016
Where did this now? This is reset at the time of the ancient Greeks. Studies have (with zigzag) walked in the right direction and a thorough understanding of the matter. This is an evil intention or is written out of desperation.
Urgent return the effects of a binary system and elements and compounds of low melting point. Water ice search 0 ° C, at temperatures of -210 ° C as ice Fe tough and is not a working compound.

Whut? Care to rephrase that so it makes (at least syntactic) sense?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.