'X' marks a curious corner on Pluto's icy plains

January 11, 2016
Transmitted to Earth on Dec. 24, 2015, this image from the Long Range Reconnaissance Imager (LORRI) extends New Horizons’ highest-resolution swath of Pluto to the center of Sputnik Planum, the informally named plain that forms the left side of Pluto’s “heart.” Credit: NASA/JHUAPL/SwRI

"X" marks the spot of some intriguing surface activity in the latest picture of Pluto returned from NASA's New Horizons spacecraft.

Transmitted to Earth on Dec. 24, this image from the Long Range Reconnaissance Imager (LORRI) extends New Horizons' highest-resolution views of Pluto to the very center of Sputnik Planum, the informally named icy plain that forms the left side of Pluto's "heart" feature.

Sputnik Planum is at a lower elevation than most of the surrounding area by a couple of miles, but is not completely flat. Its surface is separated into cells or polygons 10 to 25 miles (16 to 40 kilometers) wide, and when viewed at low sun angles (with visible shadows), the cells are seen to have slightly raised centers and ridged margins, with about 100 yards (100 meters) of overall height variation.

Mission scientists believe the pattern of the cells stems from the slow thermal convection of the nitrogen-dominated ices that fill Sputnik Planum. A reservoir that's likely several miles or kilometers deep in some places, the solid nitrogen is warmed at depth by Pluto's modest internal heat, becomes buoyant and rises up in great blobs, and then cools off and sinks again to renew the cycle.

"This part of Pluto is acting like a lava lamp," said William McKinnon, deputy lead of the New Horizons Geology, Geophysics and Imaging team, from Washington University in St. Louis, "if you can imagine a as wide as, and even deeper than, the Hudson Bay."

Computer models by the New Horizons team show that these blobs of overturning solid nitrogen can slowly evolve and merge over millions of years. The ridged margins, which mark where cooled nitrogen ice sinks back down, can be pinched off and abandoned. The "X" feature is likely one of these—a former quadruple junction where four convection meet. Numerous, active triple junctions can be seen elsewhere in the LORRI mosaic.

Explore further: A full view of Pluto's stunning crescent from New Horizons

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Eikka
4.8 / 5 (4) Jan 11, 2016
If you were to stand on that in a space suit, what would happen to your shoes?

Obviously it's really cold, so the question is really, are space suit shoes designed for direct contact with solid nitrogen?

My guess is that you'd start a geysir of boiling gas with each step, because the spacesuit is so much hotter that it would be like a lava golem walking over a rain puddle.
baudrunner
5 / 5 (3) Jan 11, 2016
Pluto's sole inhabitant, the rare but not very elusive, giant slug, Aplysia Giganticus, deliberates the fork in the road ahead.
antigoracle
3 / 5 (2) Jan 11, 2016
Pluto's sole inhabitant, the rare but not very elusive, giant slug, Aplysia Giganticus, deliberates ....

Hmm....I know that X is here, somewhere...
antialias_physorg
4 / 5 (4) Jan 11, 2016
My guess is that you'd start a geysir of boiling gas with each step

Depends on the insulation. If you have ceramic soles or a vacuum insulation layer then nothing would happen

If the soles are too 'hot' then the gas would make you lose all traction and you'd land on your ass.

But as you can see in this video: Touching a very cold ice (in this case carbon dioxide) doesn't cause plumes of gas to form if you're even minimally insulated (in this case with a simple leather glove). Granted solid CO2 is 140° warmer than solid N2 at standard pressure. Still, I think you won't need very tricky insulation to walk on a nitrogen glacier (you might want spikes, though).

https://www.youtu...Qfc6Ggis

There's also videos on youtube showing solid nitrogen ice that is quite stable in a vacuum (despite being in non-refrigerated room otherwise). So a vacuum insulation will work.
Valentiinro
not rated yet Jan 12, 2016
Pluto's sole inhabitant, the rare but not very elusive, giant slug, Aplysia Giganticus, deliberates the fork in the road ahead.

It looks like a slug to me too, cheers lol.
Tuxford
1 / 5 (1) Jan 12, 2016
Pluto's sole inhabitant, the rare but not very elusive, giant slug, Aplysia Giganticus, deliberates the fork in the road ahead.


Appears to have substantial vertical height. A structure casting a shadow? Maybe a weather station with antenna array?
EnsignFlandry
not rated yet Jan 12, 2016
The slug is a scout for the Imperial Galactic Survey Corps. They are concerned about the New Horizons probe being followed up by a manned base.

Seriously, this feature is interesting, would like to see it in other EM bands.
baudrunner
not rated yet Jan 12, 2016
No, wait! Nessie!

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