[meteorite-list] Secrets Behind Pluto's Pastels Far From Being Answered

[Ron Baalke]

http://spaceflightnow.com/2015/09/24/secrets-behind-plutos-pastels-far-from-being-answered/

Secrets behind Pluto's pastels far from being answered
by Stephen Clark
Spaceflight Now
September 24, 2015

[Image]
In this extended color image of Pluto taken by NASA's New Horizons spacecraft, 
rounded and bizarrely textured mountains, informally named the Tartarus 
Dorsa, rise up along Pluto's day-night terminator and show intricate 
but puzzling patterns of blue-gray ridges and reddish material in between. 
This view, roughly 330 miles (530 kilometers) across, combines blue, red 
and infrared images taken by the Ralph/Multispectral Visual Imaging Camera 
(MVIC) on July 14, 2015, and resolves details and colors on scales as 
small as 0.8 miles (1.3 kilometers). Credits: NASA/JHUAPL/SWRI

Geologists said Thursday they are bewildered by images from NASA's New 
Horizons spacecraft baring unseen landscapes on Pluto with unexpected 
"snakeskin" textures, colorful chasms routing through ancient landforms, 
and vivid new views of apparent glacial flows.

One close-up of a set of aligned ridges near Pluto's day-night terminator, 
which was at sunset when New Horizons encountered Pluto, has scientists 
puzzled.

"It's a unique and perplexing landscape stretching over hundreds of 
miles," said William McKinnon, New Horizons' geology, geophysics and 
imaging team deputy lead from Washington University in St. Louis. "It 
looks more like tree bark or dragon scales than geology. This'll really 
take time to figure out; maybe it's some combination of internal tectonic 
forces and ice sublimation driven by Pluto's faint sunlight."

The latest images released Thursday add high-resolution color to the black 
and white pictures previously downlinked from New Horizons, which swept 
past Pluto on July 14 to give humans their first up close views of the 
faraway world.

Scientists used data from a the MVIC color camera inside the probe's 
Ralph instrument to create a global view of Pluto. Information collected 
through the camera's blue, red and infrared filters show variations 
in Pluto's complex terrains, and scrolling across the 6.4 million pixel 
image reveals countless distinct features - craters, channels and vast 
ice fields - each with their own convoluted history.

"This image consumed the better part of this week for me," tweeted 
Alex Parker, a planetary scientist at the Southwest Research Institute. 
"I removed striping noise and deconvolved the images, massively improving 
sharpness."

[Image]
NASAs New Horizons spacecraft captured this high-resolution enhanced 
color view of Pluto on July 14, 2015. The image combines blue, red and 
infrared images taken by the Ralph/Multispectral Visual Imaging Camera 
(MVIC). Credit: Credit: NASA/JHUAPL/SWRI

The colors are stretched and do not represent what the human eye would 
see, but scientists say they are useful to bring out different types of 
terrain dotting Pluto.

"We used MVIC's infrared channel to extend our spectral view of Pluto," 
said John Spencer, a geology, geophysics and imaging team deputy lead 
from SWRI in Boulder, Colorado. "Pluto's surface colors were enhanced 
in this view to reveal subtle details in a rainbow of pale blues, yellows, 
oranges, and deep reds. Many landforms have their own distinct colors, 
telling a wonderfully complex geological and climatological story that 
we have only just begun to decode."

Scientists likened the Pluto's spectacular colors to a "red velvet 
cupcake with cream cheese frosting."

You can view the nearly 70-megabyte image in full resolution on NASA's website.
http://www.nasa.gov/sites/default/files/thumbnails/image/crop_p_color2_enhanced_release.png

"Click that link," Parker posted to his Twitter account. "Zoom in. 
This image is unlike anything you have ever seen."

NASA also released the sharpest views yet of Pluto from New Horizons' 
telescopic LORRI camera, which takes pictures in black and white.

"These images - the highest-resolution yet available of Pluto - 
reveal features that resemble dunes, the older shoreline of a shrinking 
glacial ice lake, and fractured, angular water ice mountains with sheer 
cliffs," NASA said in a press release. "Color details have been added 
using MVIC's global map shown above."

[Image]
High-resolution images of Pluto taken by NASA's New Horizons spacecraft 
just before closest approach on July 14, 2015, reveal features as small 
as 270 yards (250 meters) across, from craters to faulted mountain blocks, 
to the textured surface of the vast basin informally called Sputnik Planum. 
Enhanced color has been added from the global color image. This image 
is about 330 miles (530 kilometers) across. Credit: NASA/JHUAPL/SWRI

Parker said combining data from the black and white LORRI imager and MVIC 
color camera was painstaking because the images were taken from different 
orientations.

"This means going in by hand, determining the size, shape, height, and 
features of each mountain, and stretching and warping them to match," 
he said on Twitter. "My eyes hurt, but I think the result paid off."

Scientists said the closer look at Sputnik Planum, a giant ice field the 
size of Texas, shows it is covered in previously unresolved pits and bumpy 
terrain. The textures could be dunes of ice particles.

Newly-downlinked data from New Horizons may have moved scientists closer 
to answering what makes up the icy plains of Sputnik Planum, which makes 
up the western lobe of a bright heart-shaped feature spotted by the probe 
on approach to Pluto.

An infrared spectrometer aboard New Horizons mapped concentrations of 
methane on the dwarf planet, and the results show an uneven distribution. 
Sputnik Planum appears to be rich in methane, while darker, older material 
to the southwest in an area informally named Cthulhu Regio has relatively 
little methane.

Matching the methane data with the global map of Pluto shows more methane 
in regions appearing brighter in color imagery, but scientists are not 
sure how the results are correlated.

"It's like the classic chicken-or-egg problem," said Will Grundy, 
New Horizons surface composition team lead from Lowell Observatory in 
Flagstaff, Arizona. "We're unsure why this is so, but the cool thing 
is that New Horizons has the ability to make exquisite compositional maps 
across the surface of Pluto, and that'll be crucial to resolving how 
enigmatic Pluto works."

Researchers expect all of the Pluto flyby data to be on the ground in 
late 2016 - a limitation imposed by the spacecraft's 3 billion mile 
distance from Earth. Only then will the New Horizons science team begin 
to fully piece together how the distant world's climate and geology 
interact.

Scientists will attempt to learn how Pluto changes with its 6.4-day rotation 
and decades-long seasons as the dwarf planet circuits the sun every 248 
years.

"With these just-downlinked images and maps, we've turned a new page 
in the study of Pluto beginning to reveal the planet at high resolution 
in both color and composition," said Alan Stern, New Horizons' principal 
investigator from the Southwest Research Institute. "I wish Pluto's 
discoverer Clyde Tombaugh had lived to see this day."