Pluto's blue skies, water ice revealed in new photos

Pluto's blue skies, water ice revealed in new photos

(NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

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SALT LAKE CITY — New photos of everyone's favorite dwarf planet continue to dazzle researchers back on Earth.

The first color photos of Pluto's high-altitude haze recently made their way back to NASA, appearing as a brilliant blue layer surrounding the dwarf planet. The images, which were released Thursday, replicate the color the human eye would see, according to researchers working on the New Horizons project.

"Who would have expected a blue sky in the Kuiper Belt? It's gorgeous," New Horizons principal investigator Alan Stern said in a statement.

Amazing! Blue Skies and Water Ice found on #Pluto. Enjoy! :-) — NASA New Horizons (@NASANewHorizons) October 8, 2015

Researchers said they believe the haze particles are actually gray or red, but break apart and react with each other high in the atmosphere. Those particles then recombine and are coated with ice frost before falling back to Pluto's surface. A similar process has been observed on Saturn's moon Titan.

"That striking blue tint tells us about the size and composition of the haze particles," science team researcher Carly Howett said in a statement. "A blue sky often results from scattering of sunlight by very small particles. On Earth, those particles are very tiny nitrogen molecules. On Pluto they appear to be larger — but still relatively small — soot-like particles we call tholins."

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The new photos also revealed small regions on the dwarf planet that have exposed water ice, according to NASA. Curiously, those spots appear to be bright red.

"I'm surprised that this water ice is so red," science team member Silvia Protopapa said in a statement. "We don't yet understand the relationship between water ice and the reddish tholin colorants on Pluto's surface."

Scientists are working to determine why water appears in these small regions, but not in other large expanses.


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Natalie Crofts


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