From mountains to moons—multiple discoveries from New Horizons Pluto mission

From mountains to moons—multiple discoveries from NASA’s New Horizons Pluto mission
New close-up images of a region near Pluto’s equator reveal a giant surprise -- a range of youthful mountains rising as high as 11,000 feet (3,500 meters) above the surface of the icy body. Credit: NASA/JHU APL/SwRI

Icy mountains on Pluto and a new, crisp view of its largest moon, Charon, are among the several discoveries announced Wednesday by NASA's New Horizons team, just one day after the spacecraft's first ever Pluto flyby.

"Pluto New Horizons is a true mission of exploration showing us why basic scientific research is so important," said John Grunsfeld, associate administrator for NASA's Science Mission Directorate in Washington. "The mission has had nine years to build expectations about what we would see during closest approach to Pluto and Charon. Today, we get the first sampling of the scientific treasure collected during those critical moments, and I can tell you it dramatically surpasses those high expectations."

"Home run!" said Alan Stern, principal investigator for New Horizons at the Southwest Research Institute (SwRI) in Boulder, Colorado. "New Horizons is returning amazing results already. The data look absolutely gorgeous, and Pluto and Charon are just mind blowing."

A new close-up image of an equatorial region near the base of Pluto's bright heart-shaped feature shows a mountain range with peaks jutting as high as 11,000 feet (3,500 meters) above the surface of the icy body.

The mountains on Pluto likely formed no more than 100 million years ago—mere youngsters in a 4.56-billion-year-old solar system. This suggests the close-up region, which covers about one percent of Pluto's surface, may still be geologically active today.

"This is one of the youngest surfaces we've ever seen in the solar system," said Jeff Moore of the New Horizons Geology, Geophysics and Imaging Team (GGI) at NASA's Ames Research Center in Moffett Field, California.  

From mountains to moons—multiple discoveries from New Horizons Pluto mission
Remarkable new details of Pluto’s largest moon Charon are revealed in this image from New Horizons’ Long Range Reconnaissance Imager (LORRI), taken late on July 13, 2015 from a distance of 289,000 miles  (466,000 kilometers). 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. Mission scientists are surprised by the apparent lack of craters on Charon. South of the moon’s equator, at the bottom of this image, terrain is lit by the slanting rays of the sun, creating shadows that make it easier to distinguish topography. Even here, however, relatively few craters are visible, indicating a relatively young surface that has been reshaped by geologic activity. In Charon’s north polar region, a dark marking prominent in New Horizons’ approach images is now seen to have a diffuse boundary, suggesting it is a thin deposit of dark material. Underlying it is a distinct, sharply bounded, angular feature; higher resolution images still to come are expected to shed more light on this enigmatic region. The image has been compressed to reduce its file size for transmission to Earth. In high-contrast areas of the image, features as small as 3 miles (5 kilometers) across can be seen. Some lower-contrast detail is obscured by the compression of the image, which may make some areas appear smoother than they really are. The uncompressed version still resides in New Horizons’ computer memory and is scheduled to be transmitted at a later date. The image has been combined with color information obtained by New Horizons’ Ralph instrument on July 13. Credit: NASA-JHUAPL-SwRI

Unlike the icy moons of giant planets, Pluto cannot be heated by gravitational interactions with a much larger planetary body. Some other process must be generating the mountainous landscape.

"This may cause us to rethink what powers geological activity on many other icy worlds," says GGI deputy team leader John Spencer at SwRI.

Pluto
Pluto nearly fills the frame in this image from the Long Range Reconnaissance Imager (LORRI) aboard NASA’s New Horizons spacecraft, taken on July 13, 2015 when the spacecraft was 476,000 miles (768,000 kilometers) from the surface. This is the last and most detailed image sent to Earth before the spacecraft’s closest approach to Pluto on July 14. The color image has been combined with lower-resolution color information from the Ralph instrument that was acquired earlier on July 13. This view is dominated by the large, bright feature informally named the “heart,” which measures approximately 1,000 miles (1,600 kilometers) across. The heart borders darker equatorial terrains, and the mottled terrain to its east (right) are complex. However, even at this resolution, much of the heart’s interior appears remarkably featureless—possibly a sign of ongoing geologic processes. Credit: NASA/APL/SwRI

The new view of Charon reveals a youthful and varied terrain. Scientists are surprised by the apparent lack of craters. 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. The image also shows a canyon estimated to be 4 to 6 miles (7 to 9 kilometers) deep. In Charon's north polar region, the dark surface markings have a diffuse boundary, suggesting a thin deposit or stain on the surface.

From mountains to moons—multiple discoveries from New Horizons Pluto mission
Since its discovery in 2005, Pluto's moon Hydra has been known only as a fuzzy dot of uncertain shape, size, and reflectivity. Imaging obtained during New Horizons' historic transit of the Pluto-Charon system and transmitted to Earth early this morning has definitively resolved these fundamental properties of Pluto's outermost moon. Long Range Reconnaissance Imager (LORRI) observations revealed an irregularly shaped body characterized by significant brightness variations over the surface. With a resolution of 2 miles (3 kilometers) per pixel, the LORRI image shows the tiny potato-shaped moon measures 27 miles (43 kilometers) by 20 miles (33 kilometers). Like that of Charon, Hydra's surface is probably covered with water ice, the most abundant ice in the universe. Observed within Hydra's bright regions is a darker circular structure with a diameter of approximately 6 miles (10 kilometers). Hydra's reflectivity (the percentage of incident light reflected from the surface) is intermediate between that of Pluto and Charon. "New Horizons has finally nailed the basic physical properties of Hydra," says Hal Weaver, New Horizons Project Scientist and LORRI science operations lead. "We're going to see Hydra even better in the images yet to come." Hydra was approximately 400,000 miles away from New Horizons when the image was acquired. Credit: NASA-JHUAPL-SwRI

New Horizons also observed the smaller members of the Pluto system, which includes four other moons: Nix, Hydra, Styx and Kerberos. A new sneak-peak image of Hydra is the first to reveal its apparent irregular shape and its size, estimated to be about 27 by 20 miles (43 by 33 kilometers).

The observations also indicate Hydra's surface is probably coated with water ice. Future images will reveal more clues about the formation of this and the other moon billions of years ago. Spectroscopic data from New Horizons' Ralph instruments reveal an abundance of methane ice, but with striking differences among regions across the frozen surface of Pluto.

From mountains to moons—multiple discoveries from New Horizons Pluto mission
The latest spectra from New Horizons Ralph instrument reveal an abundance of methane ice, but with striking differences from place to place across the frozen surface of Pluto. “We just learned that in the north polar cap, methane ice is diluted in a thick, transparent slab of nitrogen ice resulting in strong absorption of infrared light,” said New Horizons co-investigator Will Grundy, Lowell Observatory, Flagstaff, Arizona.  In one of the visually dark equatorial patches, the methane ice has shallower infrared absorptions indicative of a very different texture.  “The spectrum appears as if the ice is less diluted in nitrogen,” Grundy speculated “or that it has a different texture in that area.”  An Earthly example of different textures of a frozen substance:  a fluffy bank of clean snow is bright white, but compacted polar ice looks blue.  New Horizons’ surface composition team, led by Grundy, has begun the intricate process of analyzing Ralph data to determine the detailed compositions of the distinct regions on Pluto. This is the first detailed image of Pluto from the Linear Etalon Imaging Spectral Array, part of the Ralph instrument on New Horizons.  The observations were made at three wavelengths of infrared light, which are invisible to the human eye. In this picture, blue corresponds to light of wavelengths 1.62 to 1.70 micrometers, a channel covering a medium-strong absorption band of methane ice, green (1.97 to 2.05 micrometers) represents a channel where methane ice does not absorb light, and red (2.30 to 2.33 micrometers) is a channel where the light is very heavily absorbed by methane ice.  The two areas outlined on Pluto show where Ralph observations obtained the spectral traces at the right.  Note that the methane absorptions (notable dips) in the spectrum from the northern region are much deeper than the dips in the spectrum from the dark patch.  The Ralph data were obtained by New Horizons on July 12, 2015. Credit: NASA-JHUAPL-SwRI

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New Image of Pluto: 'Houston, We Have Geology'

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Jul 16, 2015
"This may cause us to rethink what powers geological activity on many other icy worlds," says GGI deputy team leader John Spencer at SwRI.


Indeed.

This object is much smaller than Mars, and much farther away from the Sun than the Triton moon(an analog nitrogen-rich object,) yet something has recently powered geology on a global scale for both Pluto and Charon.

How long do you suppose it takes a range of 2 mile high ice-mountains to form on a planet that receives pitifully little energy from the Sun? That's a hell of a glaciation event, whether it's caused by "weather" or "Geology".

I'm voting for radioactive core, because there doesn't appear to be any other power source to do this.

Jul 16, 2015
Maybe Pluto and Charon aren't as old as the other objects in the Solar System?

Could it have formed AFTER the Late Heavy Bombardment?

It will be interesting to see what the isotopic ratios are for the hydrogen and oxygen in the Methane-ice and Water-ice, because that may provide a clue as to when and where the system formed, if it's different than expected.

Maybe it still accretes enough dust and gas from its slowly evolving orbit to power new geology?

Jul 16, 2015
Why do the contiguous mountains form in blobs and ripples, instead of elongated chains like on Earth?

Why is that pair of mountains in the middle of a giant plainscape, isolated from all the other mountains?

Seems to suggest three different geologic processes at work.

1) Isolated mountains in the middle of the plains (left side).
2) "Bubbly" blobular mountain range (Middle)
3) "Wavy" structure with 4 highlands and 3 valleys (bottom right)

4) There looks like very small alluvial fans at the base of those "wavy" hill things, which may suggest liquid nitrogen rivers have existed there before. Where did the energy come from, since the planet is way below the freezing point of Nitrogen? Heck Triton is below the freezing point of nitrogen...

Jul 16, 2015
There's gonna be an orbiter mission. You can bet on that.

First they'll send orbiters to Uranus and Neptune (already planned) and more orbiters to Jupiter and Saturn (already planned), but you can bet with this freaking UNIQUE geology that we can see from just the few photos we have so far, NASA is going to want another mission to study this planet more closely, eventually. It'll be a few decades though, but most likely within my lifetime. The pattern for planets beyond Mars is 1 orbiter mission per 2 decades.

After Ceres looked like a Queue-ball with a few holes poked in it, I expected much the same from Pluto and Charon. I didn't expect to see evidence of several different geologic processes and potentially liquid nitrogen "rain" (at some point) all in the same still photograph.

Jul 16, 2015
Why do the contiguous mountains form in blobs and ripples, instead of elongated chains like on Earth?

Why is that pair of mountains in the middle of a giant plainscape, isolated from all the other mountains?

Plate tectonics.

(And we also have a lot of isolated mountains on Earth. You might want to peruse a map or a globe once in a while)

Jul 16, 2015
Why do the contiguous mountains form in blobs and ripples, instead of elongated chains like on Earth?

Why is that pair of mountains in the middle of a giant plainscape, isolated from all the other mountains?

Plate tectonics.

(And we also have a lot of isolated mountains on Earth. You might want to peruse a map or a globe once in a while)


Isolated mountains on Earth are caused by volcanism (usually super-plumes) powered by Uranium in the Earth's core and Mantle.

Mean density suggests that even though it likely has a rock/metallic core, it would be very small relative to the planet's entire volume.

I did say that I think internal radioactivity is the main driver here, but those formations don't look like Earth mountain chains.

There is one exception, east of the Caribbean on Earth there is a sub-oceanic mountainous region that has some similarities to that structure. However, Earth's core alone is more massive and energetic than Pluto.

Jul 16, 2015
I can't wait to see the uncompressed version of that Charon photograph, because this is ridiculous.

For where they are located in the Kuiper Belt, you would expect both of these objects to be as cratered as a Swiss cheese, and instead that thing looks remarkably smooth with only a few small craters. In this compressed photo they look...weathered... almost...but perhaps it is not so in the uncompressed version.

I think we can explain "weathering" on Charon, since Charon apparently captures some of Pluto's lost Nitrogen. This "Nitrogen snow" could be providing some energy to smooth out the surface a bit.

You know, the stereotype of this region of space is a bunch of things that hit one another from time to time and go haywire, etc, like the Asteroid Belt, but these photos make it look like Pluto and Charon only actually get hit by something of significant size once in a very long time.

Surely they haven't been struck by anything bigger than a few kilometers in eons.

Jul 16, 2015
powered by Uranium in the Earth's core

Ever heard of subduction zones?
Ever heard of volcanism creatd by impacts?
Ever heard of volcanoes being triggered by Earthquakes?
...there's quite a few things that can cause volcanoes.

They're even tossing the idea of a subsurface ocean around.

So let's not go for the "looks like a duck" approach, here. That's the EU crowd's fallacy.

Jul 16, 2015
Top-left face of the bottom-center ripple-mountain (the one left of the bottom-center shadow and valley).

Look closely. Those are alluvial fans. It looks like something liquid flowed down that side of the structure and then re-froze as it got to the bottom. It has some similarities to basaltic lava flows (Hawaii) and some similarities to alluvial fans.

It's as if Pluto is more geologically active than Mars, and that isn't supposed to be happening with any geology we know if Pluto is the same age as the other planets.

They're damn right they're going to have to re-think how this works on ice worlds.

I can stretch my brain a bit, but that's a big deal. At those temperatures the ices are frozen as hard a steel on Earth.

I think that fan is more impressive than the mountains themselves, because it means the geologic processes (or "weather" whatever caused it) happened in multiple stages. That is to say, if it's volcanic, it erupted multiple times...relatively recently.

Jul 16, 2015
Okay, the Appalachian mountains in the U,S. could be an analog to the wavy mountain structure in the bottom right (4 highlands/ridges and 3 valleys), but on Earth that was caused by a collision between North America and an exposed dome of Mantle Rock (still found in Canada) as well as another piece of continental crust and a piece of oceanic crust slamming into the same region. And of course the crust completely folded over onto itself on Earth, burying entire forests, and producing the massive Coal deposits in the Carolinas.

Where does the energy come from to do that on a 40k ball of nitrogen and methane ice with a mean density of 1.6g/cm^3? (which is about the same as CO2 ice).

Jul 16, 2015
powered by Uranium in the Earth's core

Ever heard of subduction zones?
Ever heard of volcanism creatd by impacts?
Ever heard of volcanoes being triggered by Earthquakes?
...there's quite a few things that can cause volcanoes.

They're even tossing the idea of a subsurface ocean around.

So let's not go for the "looks like a duck" approach, here. That's the EU crowd's fallacy.

That's funny being there is zero evidence for all which you claim to be the mechanisms, other than the results. Admit it, the data flies in the face of the "predictions" of the ST which you wholeheartedly defend without compunction. All of the reasoning you rely on is "dark" and just out of view and unfalsifiable.

Jul 16, 2015
That's funny being there is zero evidence for all which you claim to be the mechanisms,

Seriously? No evidence? Have ever even looked at a map of the planet you live on? Ever notice where the volcanoes are?

Jeeez, man. You really are trying hard to make yourself look dumb in the smallest possible time, aren't you?

Jul 16, 2015
Jeez man, the article is about Pluto, and that's what I'm talking about. I don't see any plates, or subduction zones in the images above.

Jul 17, 2015
We were talking about mechanisms on Earth. Try to keep up.

Jul 17, 2015
Jeez man, the article is about Pluto, and that's what I'm talking about. I don't see any plates, or subduction zones in the images above.


Well, if you don't see it at this distance then it surely isn't there... Another interesting mechanism that can account for geologic features is collapse and subduction due to outgassing. On approach they did confirm Nitrogen escaping Pluto. This is one of several theorized mechanisms for Enceladus' internal heat. That mass loss causes voids which are collapsed along fissure lines where gravitational contraction attempts to round out the satellite causing subduction and heating allowing the formation of liquid water.

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