That's part of a picture from New Horizons: a sample from the highest-resolution images the spacecraft has started sending back.We're pretty sure that the mountains are frozen water, and the flat parts softer "ice:" probably including frozen nitrogen.
The first journal paper using New Horizons' flyby data was published in October: but there's a great deal left to study, and even more still stored on New Horizons. (November 13, 2015)
Other scientists think they've found evidence that those bright spots in Occator Crater are frozen water, exposed when something hit Ceres. If they're right, the impact happened recently. I'll get back to that.
- Bright Spots on Ceres: Icy Divots?
- Highest-Resolution Images of Pluto
- A Mile-High Cliff and Plutonian Badlands
(From NASA/APL/Southwest Research Institute, used w/o permission.)
(New Horizons position at 0300 UTC December 11, 2015/1900 Central Time December 10, 2015 (CT))
Maps and History
(From JPL/NASA, used w/o permission.)
(Map of Pluto, showing unofficial names used by the New Horizons team. The International Astronomical Union (IAU) hasn't decided what the official names will be.)
(From JPL/NASA, used w/o permission.)
(Part of the same map, large enough to read the names. We've gotten a closer look at the al-Idrisi Montes, and other areas.)
We've developed naming conventions for features on other planets. One mountain is a mons, a mountain range is a montes: so the al-Idrisi Montes are the al-Idrisi Mountains. If you thought "al-Idrisi" doesn't sound British, you'd be right.
I gather that the mountain range bordering Sputnik Planum is named after Muhammad al-Idrisi, an Almoravid explorer who lived about nine centuries back. He was born in Ceuta, an urban peninsula on Morocco's northeast coast.Over the last couple dozen centuries, it's been run by Carthaginians, Romans, Vandals, Visigoths, the Byzantine Empire and assorted other folks. Spain is in possession at the moment, and a millennium from now it'll most likely be in other hands.
The Almoravid dynasty was running Ceuta in al-Idrisi's day, which may or may not be why he lived at the court of Sicily's Roger II in Plaermo for much of his adult life.
Roger was a Norman: the same lot that conquered England about a thousand years back. They're still in charge there, more or less. Normans are, or were, French-speaking Vikings: and that's another topic.
Getting back to al-Idrisi, he's chiefly known for a collection of maps, the Tabula Rogeriana, and Nuzhat al-Mushtaq, a compendium of geographical information and maps.
Depending on who you read, Nuzhat al-Mushtaq's title translates as "The book of pleasant journeys into faraway lands," or "The pleasure of him who longs to cross the horizons."
Folks on the New Horizons liked the second translation, which apparently is why they named a mountain range after him. ("Pluto Name Bank Proposal 2015-07-07," via docs.google.com)
Reviewing stuff I'd written about Pluto, I found several posts about Pluto and extraterrestrial life: real and imagined. (July 31, 2015; July 24, 2015; July 10, 2015)
Frank R. Paul's Pluto People, Faith, and Science
(From Frank R. Paul, via Fabio Feminò and David S. Zondy, used w/o permission.)(Frank R. Paul's very-imaginary people on Pluto, 1930s.)
If you've read these posts before, you know why I'm not upset that we're learning more about this wonder-filled universe. Go ahead: skip down to Bright Spots on Ceres: Icy Divots?, go for a walk, get some coffee; or keep reading. I'll try to be brief.
Faith, in the Catholic sense, is not reason: but it's not unreasonable. (Catechism of the Catholic Church, 159)
Since I believe that the things of faith come from God, that God created the world, and is Truth — fearing knowledge of God's world would be illogical.
Truth cannot contradict truth. (Catechism, 156-159)
Studying this astounding creation is part of being human. (Catechism, 159, 2293-2295)
Scientific discoveries are invitations "...to even greater admiration for the greatness of the Creator...." (Catechism, 283, 341)
The Catholic Church's view of science makes sense, since we're told that truth is very important. (Catechism, Prologue, 27, 74, more under Truth in the index)
Seeking truth and seeking God are compatible. So are faith and reason. (Catechism, 35, 50, 154, 274, 1706)
More about science and getting a grip:
- "Faith, Fear, and Flying Saucers"
(August 2, 2015)
"The Universe: a Magnificent Tent" - "Humility, Science, and Accepting Reality"
(March 29, 2015)
(June 14, 2015)
1. Bright Spots on Ceres: Icy Divots?
(From NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, via BBC News, used w/o permission.)
("The Occator Crater has the most impressive collection of bright spots"
(BBC News))
"Explanation for Ceres' mystery bright spots"I've talked about Ceres and Dawn, the first spacecraft to orbit two asteroids or planets other than Earth, before. (September 4, 2015; March 13, 2015)
Jonathan Amos, BBC News (December 9, 2015)
"It has been the big Solar System mystery of 2015 - what are the bright spots on Ceres, the largest object in the asteroid belt between Mars and Jupiter?
"Scientists think they now have some answers.
"They are places where impacts have excavated a briny layer of water-ice under the dwarf planet's surface, the researchers tell the journal Nature.
"And the very brightest features are the youngest, freshest exposures...."
Occator Crater's bright spots weren't the first mystery about what's on and in Ceres. It's nowhere near as dense as it should be. Ceres' density is roughly 2 (2.16) grams per cubic centimeter: compared to about 3.4 grams per cubic centimeter for Vesta, and 5.5 for Earth.
Water vapor observed near Ceres suggested that quite a bit of it might be water. (January 24, 2014)
That's why scientists suggested that the bright spots might be water ice: maybe from a water 'volcano,' more likely a divot from a recent impact. But thinking they might be water ice, and having evidence to back up the idea, aren't the same thing.
I'll be back, after two images from NASA, JPL, UCLA, MPS, DLR, and IDA. That's a lot of acronyms. IDA may stand for for Institute for Defense Analyses Science and Technology Policy Institute, Iterative deepening A*, which doesn't make sense in this context — or something else.
(From NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, used w/o permission.)
("...This view is a composite of two images of Occator: one using a short exposure that captures the detail in the bright spots, and one where the background surface is captured at normal exposure...."
(Martin Perez, NASA))
(From NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, via JPL-Caltech, used w/o permission.)
(Occator Crater on Ceres. A slight haze form over the crater's bright spots when sunlight heats the area. The haze is visible when Occator is very near the horizon, as in this image from Dawn.)
The science team had programmed the Dawn's cameras for picture-taking of Ceres' generally-dark surface. That's why the Occator Crater bright spots looked like they were glowing in early images:
"...'We said, 'Wow! What's that? We didn't expect this,' recalls Andreas Nathues, the camera's principal investigator.Some of the other bright spots are about the right brightness to be magnesium sulfate, Epsom salt, but water ice is the best bet for the Occator spots. It's not just how bright they are: if they're exposed water ice, the water would be sublimating, turning directly to gas, escaping into space and taking bits of dust with it.
" 'The reflectivity is in the order of 0.25, which means about 25% of the light is reflected; and in the inner core centre [of the Occator spot collection] it's even more - up to 50-60% of the light is reflected; while the remaining surface is rather dark - the average is about 9%,' said the scientist from the Max Planck Institute for Solar System Research in Goettingen, Germany...."
(Jonathan Amos, BBC News)
Sure enough, there's a slight haze over the spots when sunlight hits them: not much, but enough to see when Occator is near the horizon. If they're water ice, exposed when something hit Ceres recently, they'll be fading as the ice sublimates.
2. Highest-Resolution Images of Pluto
(From NASA/JHUAPL/SwRI, used w/o permission.)
("The Mountainous Shoreline of Sputnik Planum: In this highest-resolution image from NASA's New Horizons spacecraft, great blocks of Pluto's water-ice crust appear jammed together in the informally named al-Idrisi mountains...."
(NASA))
"New Horizons Returns First of the Best Images of Pluto"
Tricia Talbert, NASA (December 4, 2015)
"NASA's New Horizons spacecraft has sent back the first in a series of the sharpest views of Pluto it obtained during its July flyby – and the best close-ups of Pluto that humans may see for decades.
"Each week the piano-sized New Horizons spacecraft transmits data stored on its digital recorders from its flight through the Pluto system on July 14. These latest pictures are part of a sequence taken near New Horizons' closest approach to Pluto, with resolutions of about 250-280 feet (77-85 meters) per pixel - revealing features less than half the size of a city block on Pluto's diverse surface. In these new images, New Horizons captured a wide variety of cratered, mountainous and glacial terrains. ..."
Pluto isn't particularly dense, either: 1.87 grams per cubic centimeter, on average; compared to Ceres' 2.16.That's enough to compress its interior to a solid — or liquid. Scientists figure the planet/dwarf planet/Kuiper belt object/whatever had enough radioactive elements in the original mix to heat the interior: at least for a while.
That would have allowed heavy materials to sink, giving Pluto a layered interior.
Crunching the numbers, they came up with an educated guess about what's inside Pluto: a rocky core; surrounded by water ice, and maybe liquid water if the core's still warm enough; then mostly frozen nitrogen on top.
That's an educated guess, though. There's a great deal left to learn: like what pushed up those mountains, what's eroding them, and exactly what are they made of?
3. A Mile-High Cliff and Plutonian Badlands
(From NASA/JHUAPL/SwRI, used w/o permission.)
"Pluto's 'Badlands' "We know more about Pluto than we did before the New Horizons flyby, but as I said: there's a great deal left to learn, like why part of Pluto's northern hemisphere looks so much like Triton.
Tricia Talbert, NASA (December 4, 2015)
"This highest-resolution image from NASA's New Horizons spacecraft shows how erosion and faulting has sculpted this portion of Pluto’s icy crust into rugged badlands. The prominent 1.2-mile-high cliff at the top, running from left to upper right, is part of a great canyon system that stretches for hundreds of miles across Pluto’s northern hemisphere. New Horizons team members think that the mountains in the middle are made of water ice, but have been modified by the movement of nitrogen or other exotic ice glaciers over long periods of time..."
There's the matter of deciding what names get assigned to Plutonian features, too. I talked about names, the IAU, donuts, and Dublin, in another post. (July 24, 2015)
About Pluto's al-Idrisi mountains, names, and vaguely-related topics — I did that, too. Right.
Next, a link list for stuff you don't need — or maybe want — to know about Pluto. I recommend the JPL/NASA piece, though: it includes a slightly-spectacular mosaic of images, from Pluto's horizon to Sputnik Planum, that may have another name by this time next year:
- Wikipedia
- NASA
- "The Mountainous Shoreline of Sputnik Planum"
ricia Talbert(December 4, 2015) - "New Horizons' Very Best View of Pluto (Mosiac)" ["Mosiac??" That's how they spelled it]
JPL/NASA (December 4, 2015)
- "The Mountainous Shoreline of Sputnik Planum"
- "Pluto's Cup-Capped Mountains"
(November 13, 2015)
Particularly - "New Horizons and Ceres"
(September 4, 2015)
Particularly - "Pluto, Earth 2.0, and Life in the Universe"
(July 31, 2015)
Particularly - "Pluto's Unexpected Terrain; SETI, Radio, and Drums"
(July 24, 2015)
Particularly - "Dawn's Arrival at Ceres; Sims and 'Chaos' "
(March 13, 2015)
Particularly
2 comments:
I'm glad I learned a little more about Pluto.
The Cosmos fascinates me.
In my humble way, I became more rich in my knowledge.
Ilídia SoaresLopes
Thank you, Unknown.
The universe is filled with wonders. The trick is learning to notice them. :)
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