Mysterious Mountain Revealed in First Close-up of Pluto’s Moon Charon

This new image of an area on Pluto’s largest moon Charon has a captivating feature — a depression with a peak in the middle, shown here in the upper left corner of the inset. The image shows an area approximately 240 miles (390 kilometers) from top to bottom, including few visible craters. The image was taken at approximately 6:30 a.m. EDT on July 14, 2015, about 1.5 hours before closest approach to Pluto, from a range of 49,000 miles (79,000 kilometers). Credits: NASA-JHUAPL-SwRI
Story updated[/caption]

APPLIED PHYSICS LABORATORY, LAUREL, MD – A mysterious mountain in the middle of a moat on Pluto’s biggest moon Charon, has captivated and baffled scientists leading NASA’s New Horizons mission which made history when it became the first spacecraft to visit our solar system’s most distant planet barely two days ago on Tuesday morning, July 14, 2015.

NASA released the first close-up image of Charon today (July 16), shown above, and it has the geology team scratching their heads in amazement and wonder. They can’t figure out the nature of a big mountain set inside a moat.

The new image shows a depression with a mountain peak in the middle.

“The most intriguing feature is a large mountain sitting in a moat,” said Jeff Moore with NASA’s Ames Research Center, Moffett Field, California, who leads New Horizons’ Geology, Geophysics and Imaging team. “This is a feature that has geologists stunned and stumped.”

The location of the “mountain in a moat” is shown in the inset of a global view of Charon.

The new high resolution image of Charon was taken at approximately 6:30 a.m. EDT (10:30 UTC), barely an hour and a half before the piano-shaped spacecraft’s closest approach to Pluto on July 14, 2015, from a range of only 49,000 miles (79,000 kilometers).

The image was captured by New Horizons’ high resolution Long Range Reconnaissance Imager (LORRI).

Pluto Explored at Last
The New Horizons mission team celebrates successful flyby of Pluto in the moments after closest approach at 7:49 a.m. EDT on July 14, 2015. New Horizons Principal Investigator Alan Stern of Southwest Research Institute (SwRI), Boulder, CO., left, Johns Hopkins University Applied Physics Laboratory (APL) Director Ralph Semmel, center, and New Horizons Co-Investigator Will Grundy Lowell Observatory hold an enlarged print of an U.S. stamp with their suggested update after Pluto became the final planet in our solar system to be explored by an American space probe (crossing out the words ‘not yet’) – at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. Credit: Ken Kremer/

A much sharper view is yet to come, because the image is heavily compressed.

“Sharper versions are anticipated when the full-fidelity data from New Horizons’ Long Range Reconnaissance Imager (LORRI) are returned to Earth,” say NASA officials.

Altogether it will take 16 months to transmit all the data collected by New Horizons at the Pluto system.

The area in the LORRI image comprises an area approximately 240 miles (390 kilometers) from top to bottom.

Crisp new view of Pluto’s largest moon, Charon shows a swath of cliffs and troughs stretches about 600 miles (1,000 kilometers) from left to right, suggesting widespread fracturing of Charon’s crust, likely a result of internal processes. At upper right, along the moon’s curving edge, is a canyon estimated to be 4 to 6 miles (7 to 9 kilometers) deep. Credit: NASA-JHUAPL-SwRI

Notably there are few visible craters “indicating a relatively young surface that has been reshaped by geologic activity.”

And a “swath of cliffs and troughs stretching about 600 miles (1,000 kilometers) suggests widespread fracturing of Charon’s crust, likely the result of internal geological processes,” notes the team.

The Texas-sized moon measures about 750 miles (1200 kilometers) across, about half the diameter of Pluto. Pluto spans 1,471 miles (2,368 km) across.

After a nine year voyage through interplanetary space, New Horizons barreled past the Pluto system on Tuesday, July 14 for a history making first ever flyby at over 31,000 mph (49,600 kph), and survived the passage by swooping barely 7,750 miles (12,500 kilometers) above the planet’s amazingly diverse surface at 7:49 a.m. EDT. It passed about 17,900 miles (28,800 kilometers) from Charon during closest approach.

NASA Administrator Charles Bolden congratulates the New Horizons team after successful Pluto flyby on July 14, 2015, to cheering crowd at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, during live NASA TV media briefing. Credit: Ken Kremer/

Watch for Ken’s continuing coverage of the Pluto flyby on July 14. He was onsite reporting live on the flyby and media briefing from the Johns Hopkins University Applied Physics Laboratory (APL).

New images will be released on Friday, July 17 – watch for my story.

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

Ken Kremer

Chasms, craters, and a dark north polar region are revealed in this image of Pluto’s largest moon Charon taken by New Horizons on July 11, 2015. The annotated version includes a diagram showing Charon’s north pole, equator, and central meridian, with the features highlighted. Credits: NASA/JHUAPL/SWRI
Ken Kremer

Dr. Ken Kremer is a speaker, research scientist, freelance science journalist (KSC area,FL) and photographer whose articles, space exploration images and Mars mosaics have appeared in magazines, books, websites and calendars including Astronomy Picture of the Day, NBC, FOX, BBC,, Spaceflight Now, Science and the covers of Aviation Week & Space Technology, Spaceflight and the Explorers Club magazines. Ken has presented at numerous educational institutions, civic & religious organizations, museums and astronomy clubs. Ken has reported first hand from the Kennedy Space Center, Cape Canaveral, NASA Wallops, NASA Michoud/Stennis/Langley and on over 80 launches including 8 shuttle launches. He lectures on both Human and Robotic spaceflight - Follow Ken on Facebook and Twitter

Recent Posts

Lunar Infrastructure Could Be Protected By Autonomously Building A Rock Wall

Lunar exploration equipment at any future lunar base is in danger from debris blasted toward…

8 hours ago

Why is Jupiter’s Great Red Spot Shrinking? It’s Starving.

The largest storm in the Solar System is shrinking and planetary scientists think they have…

15 hours ago

ESA is Building a Mission to Visit Asteroid Apophis, Joining it for its 2029 Earth Flyby

According to the ESA's Near-Earth Objects Coordination Center (NEOCC), 35,264 known asteroids regularly cross the…

20 hours ago

The Most Dangerous Part of a Space Mission is Fire

Astronauts face multiple risks during space flight, such as microgravity and radiation exposure. Microgravity can…

23 hours ago

Stars Can Survive Their Partner Detonating as a Supernova

When a massive star dies in a supernova explosion, it's not great news for any…

1 day ago

Swarming Satellites Could Autonomous Characterize an Asteroid

An asteroid's size, shape, and rotational speed are clues to its internal properties and potential…

1 day ago