Pluto's large moon Charon is coming into focus, and it is an intriguing world indeed.
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Pluto's large moon Charon is coming into focus, and it is an intriguing world indeed.

Pluto’s Large Moon Charon Is Stunning

Remember when we reported that Charon would probably turn out to be an astonishing world in its own right? Well, the newest image released by the New Horizons team suggests Pluto’s largest moon is absolutely that.

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Charon is a world of chasms and craters, capped by a darkened pole. NASA/JHUAPL/SwRI

In the photo, shot from less than 5 million kilometers away, the 1,200-kilometer-wide sphere appears riven with enormous canyons — at least one of which is deeper and longer than the Grand Canyon, said planetary geologist Bill McKinnon of the Washington University in St. Louis in a statement. In addition, Charon’s surface is mottled with impact craters. That alone is not surprising (in fact, craters were one of the team’s top predictions for surface features on Charon), but the size and color are intriguing. One of the crater bottoms appears darker than the surrounding surface; whether this is because it’s made of different material or is simply less reflective isn’t clear yet. And then there’s that mysteriously dark region capping the moon’s pole.

What is clear is that these images will only get better as New Horizons continues to speed toward its July 14 trip through the Pluto system. Soon, we may even be able to see the planet’s four small moons as well. (Learn more about the historic mission to Pluto on the National Geographic Channel.)

Speaking of moons, one of the predictions the team made was that New Horizons would discover at least one more moon orbiting Pluto. So far, no additional moons have been spotted. Unfortunately, that could be due to the July 4 glitch that sent New Horizons into safe mode.

“The one piece of significant science that we did lose due to the safing event was the deepest search for moons,” says team member Mark Showalter of the SETI Institute. Those data would have been taken seven days prior to closest approach. Now, the team will be searching through older data (from 13 days prior) for moons. Those images are taken from about twice as far away, though.

But all hope is not lost yet. New moons might still be discovered, Showalter says, either during the reprocessing of data taken in the last month, or if a new moon serendipitously pops up in another image.

P.S. At 11:23 p.m. tonight, New Horizons will be within a million miles of Pluto!