April 27th, 2017
Yesterday I tweeted Jason Cook and asked him about a possible scenario that might take place on Pluto.
Here's how the conversation went.
Here's how the conversation went.
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Milankovitch cycles 800 thousand years ago or every 1.4 Myr years make N2 (nitrogen) reach its triple point on Pluto creating explosions, could this spray the small satellites with ammonia hydrates but not N2 (nitrogen), CH4 (methane), or CO (carbon monoxide)?
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If that happens, probably all species would get sprayed if in solution, but N2, CH4, and CO are volatile. Low gravity on small satellites = short life
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But N2 on Pluto's surface wouldn't have much/any NH3. Buried and warmed N2 wouldn't be at vacuum. But the concept is noted and probably valid.
Thank you for the feedback Would it be OK to reference you & this conversation on a web page as I did before on NH3? http://bit.ly/2k2ANTE
Sure ..
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Video of nitrogen at triple point
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Who is Jason Cook - Planetary Astronomer & Research Scientist, Icy Worlds, Spectroscopist, Data Modling, @AstroCook At Southwest Research Institute (SwRI), I was a post-doc on the New Horizons mission. I was responsible for developing the pipeline for the MVIC (Multi-spectral Visible Imaging Camera) component of Ralph, the visible color and near infrared instrument on New Horizons. The pipeline used the instrument SPICE kernels to reconstruct the trajectory of New Horizons to remove motion distortion in the MVIC images. |
Below video demonstrates slightly better explosive reaction of N2 while at triple point.
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Jason Cook is a planetary scientist that works with NASA interpreting the data returned by New Horizons.
As a result of my conversation with Alan Stern (page 67) about the age of the small satellites and my research into the crater counting age dating method, I started asking myself a question. Are these moons as young as their surface or is there a way to explain young surface material (ammonia hydrates) on potentially old dead bodies (moons)?
The basic idea I expressed to Jason was, we know axial wobble of 24 degrees create the conditions for nitrogen on Pluto to reach it's triple point. That would probably have the effect of what is seen in the above video (gaseous explosions). This process would then splatter/spray softer ices out into space carrying ammonia hydrates along for the ride (possibly). As the material impacts the moon's, the more volatile ices evaporate away leaving behind the ammonia (NH3) which would then need 20 million years for the Sun's photon's to disassemble.
The ammonia could potentially be refreshed 7 times faster than the Sun would tear it apart as these Milankovitch cycles occur every 1.4 Myrs.
As a result of my conversation with Alan Stern (page 67) about the age of the small satellites and my research into the crater counting age dating method, I started asking myself a question. Are these moons as young as their surface or is there a way to explain young surface material (ammonia hydrates) on potentially old dead bodies (moons)?
The basic idea I expressed to Jason was, we know axial wobble of 24 degrees create the conditions for nitrogen on Pluto to reach it's triple point. That would probably have the effect of what is seen in the above video (gaseous explosions). This process would then splatter/spray softer ices out into space carrying ammonia hydrates along for the ride (possibly). As the material impacts the moon's, the more volatile ices evaporate away leaving behind the ammonia (NH3) which would then need 20 million years for the Sun's photon's to disassemble.
The ammonia could potentially be refreshed 7 times faster than the Sun would tear it apart as these Milankovitch cycles occur every 1.4 Myrs.
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This process would not require full chunks of water ice ejecting off Pluto only the fluid gasses. This could explain older moons with younger material on the surface. However, this does not explain away the red tholin impact on Nix which almost certainly was a chunk of tholin covered water ice that came from Pluto.
This red zit on Nix seems to indicate ice chunks are blown out into space as well as the softer more volatile gasses. The fact that a tholin covered chunk hit Nix in its lower orbit suggest that triple point explosions are energetic enough to place an object into the same orbital path as Nix. Consequently, Nix could then also be one of these chunks of water ice from Pluto ejected during one of these Milankovitch cycles. What we can say with some confidence, thanks to Jason, is that the idea of Pluto splattering or spray painting the moon's with nitrogen or possibly ammonia hydrates is "probably valid". If frozen gasses like N2, CO, CH4 and NH3 or even NH4+OH could be ejected off Pluto then rock hard H2O probably could be as well and Nix's red zit seems to be evidence of that fact which in turn supports the idea that Nix itself is a chunk of Pluto. This method may explain the process by which Nix and Styx were placed into orbit but then the question becomes how old are they or when did this process take place? Impacts (craters) on bodies do explain some portion of the story about age, how accurate and reliable is anyone's guess. One accurate consistent reliable fact related to impacts is that geologically dead bodies with larger sized and higher frequency impacts per area tend to be older than bodies with smaller sized and lower impact frequencies per area, that is, unless the body is in a ring of material or debris field. |
Nix with its red tholin impact zit
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If Pluto is spitting out chunks of ice every 1.4 Myrs into Nix's orbital range then all bets are off when using impacts to age date the moons just as age dating moons in the rings of Saturn would be impractical.
What does the evidence support, young or old moons?
What does the evidence support, young or old moons?
Supporting evidence for the small satellite's age's
Old Moons
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Young Moons
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Albedo is far, far brighter than other nearby old bodies
Small moons have ridiculous spin rates Small moon's Poles are not aligned with Pluto/Charon Charon’s southern hemisphere covered with fragments Nix has a red tholin impact crater Triple point of N2 creates ejective explosions Photolysis destroys NH3 in 2o Myr but it covers small moons Charon was heated to >90K in the last 100K years H2O crystalline to amorphous phase on Charon only takes 1.5 Myr Small moons are not in mean-motion resonance with Charon |
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With so many potential discrepancies found in the crater counting age dating methods and the 3 billion year variance in its results, this supportive argument for old moons is pretty much rendered inept (in my opinion).
The one thing we are then left with suggesting these moons might be old is their circular orbits but I question the strength of this concept as a supportive explanation as well. We launch satellites into circular orbits all the time here on Earth. It's not that hard and it doesn't take a long time for it to occur, all that's needed is the correct ejection velocity and viola you instantly have a small satellite in a circular orbit. Pluto's gravity is only 6% that of Earth's. |
1957 - 2008, around 6,000 satellites have been launched into orbit. These computer-generated photos show all the junk orbiting Earth.
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It is estimated there are 22,000 bits of junk in orbit around earth and we only intentionally launched 6,000 the remaining 16,000 bits are accidental space junk in circular orbits around our planet. It didn't take hundreds of thousands of years. We made this mess in a mere 50 years. This web site estimates space junk quantity greater than 166 million. For me, there are no significant supportive arguments for calling Pluto's small moons old.
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This paper ON THE IMPACT ORIGIN OF PHOBOS AND DEIMOS suggest Mar's two small moons Phobos and Deimos may have been ejected off Mars and into orbit by a collision.
Our simulations also suggest that the building blocks of Phobos and Deimos contain both impactor and Martian materials (at least 35%), most of which come from the Martian mantle (50-150 km in depth) at least 50%. |
When scientists say circular orbits indicate old age of two orbiting bodies, they are referring to two bodies that initially approached each other in space and were mutually captured by gravity. Their initial orbits would be elliptical then over time they would settle into circular orbital patterns. But objects ejected off a planet simply need the correct initial velocity and they will settle quickly into a circular orbit. Objects that don't achieve that velocity will either fall back onto the planet or get lost to space. In either case the circular orbits of Pluto/Charon would have taken place in 1-10 Myr.
While this paper "Obliquity evolution of the minor satellites of Pluto and Charon" attempts to explain away the lack of polar alignment (obliquity) of the small moons It does say the following.
The satellite system is nearly coplanar with orbital periods near (not at but close which only counts in horseshoes and hand grenades) ratios of 1:3:4:5:6, but sufficiently distinct from integer ratios relative to Charon's orbital period that the small satellites are not presently in mean-motion resonances with Charon… Over 1-10 Myr, tidal evolution should have synchronized the rotation of Pluto and Charon and then circularized their orbit, expanding the binary to its present separation.
Pluto and Charon would have settled into a circular synchronized orbit within 1-10 million years and set up conditions for making the small satellites resonate in regular single digit integer intervals, just as has occurred with Neptune/Pluto in a 2-3 resonance.
All of Tombaugh Regio and the southern area near Norgay Montes is young and freshly renewed as there are few if any impact craters. While this helps indicate surface age as being young or old it does not identify the planet's age. The albedo to a lesser degree on geologically active planets can be used to indicate youth as in the case of Sputnik Planitia's surface being frequently turned over and bright white and young because of it.
While this paper "Obliquity evolution of the minor satellites of Pluto and Charon" attempts to explain away the lack of polar alignment (obliquity) of the small moons It does say the following.
The satellite system is nearly coplanar with orbital periods near (not at but close which only counts in horseshoes and hand grenades) ratios of 1:3:4:5:6, but sufficiently distinct from integer ratios relative to Charon's orbital period that the small satellites are not presently in mean-motion resonances with Charon… Over 1-10 Myr, tidal evolution should have synchronized the rotation of Pluto and Charon and then circularized their orbit, expanding the binary to its present separation.
Pluto and Charon would have settled into a circular synchronized orbit within 1-10 million years and set up conditions for making the small satellites resonate in regular single digit integer intervals, just as has occurred with Neptune/Pluto in a 2-3 resonance.
All of Tombaugh Regio and the southern area near Norgay Montes is young and freshly renewed as there are few if any impact craters. While this helps indicate surface age as being young or old it does not identify the planet's age. The albedo to a lesser degree on geologically active planets can be used to indicate youth as in the case of Sputnik Planitia's surface being frequently turned over and bright white and young because of it.
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This however is only an indication of surface age not planet age where geological activity renews the surface but in cases where there is no renewal process (no geology) as seen on the small satellites the surface albedo being brighter is an indication of the body's age not just the surface age.
Cosmic rays and space dust darken icy bodies and over long time frames will turn the surface of a dead body darker than charcoal. Bright dead bodies are younger than dark dead bodies. A planet like Pluto being geologically alive, snows methane and as a result has a young layer of snow on an old surface so albedo and crater's help guesstimate age but are far from definitive the opposite is true for dead bodies. |
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Update February 13th, 2018
The spectroscopic chart above from NASA and to the right from the USGS Spectral Library show the classic reflectance and absorption dip patterns of water ice at 1.5 and 1.65 microns identifying the presence of crystalline water ice. A dip at 1.5, 2.0 are strong indicators of H2O the dip at 1.65 indicates the water has a crystalline structure. A dip at 2.21 (below table) would be a marker of ammonia hydrates. If the 1.65 dip didn't exist the water ice would be amorphous or without any crystallized structure. |
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In this paper
Near-Infrared Spectroscopy of Charon Possible Evidence for Cryovolcanism on KUIPER BELT OBJECTS July 2007
When water ice is warmed to temperatures > 78 K it crystallizes, it only retains its crystalline structure on geologically short timescales (<1 Gyr). Given the typical heliocentric distances of KBOs, it is not possible to achieve such surface temperatures by solar heating alone. In addition to the mystery of how crystalline ice is created, there is the question of how it survives. The e-folding time for the amorphization of crystalline water ice by cosmic rays is about 1.5 Myr (Cooper et al. 2003) down to depths typically probed by infrared observations. Thus crystalline water ice must be replenished on these comparable, geologically short, timescales. In addition, ammonia hydrates are known to be decomposed by cosmic rays (Strazzulla & Palumbo 1998), such that their presence on the surface of an icy moon provides corroborating (although less restrictive) evidence for surface renewal.
I created the below table from info contained in the above paper, it shows larger bodied objects like Pluto can hold onto lighter volatile gasses like methane (CH4). Medium bodied objects like Charon loose their more volatile gasses and tend to exhibit water ices that are crystalline in structure while small bodied objects tend to have water ices that are amorphous (lacking the 1.65 micron dip). Funny thing about Pluto's small satellites, their surfaces are crystalline water ice as they have the 1.65 micron dip, meaning their surfaces were heated to greater than 78 K in the last 1.5 myr. Combine that info with the photo sensitive and photo disassembled NH3 on their surface's and it strongly suggest these are chunks of ice ejected from Charon and/or Pluto.
Some process related to the medium body size's appears to form crystalline ice on times scales less than 1.5 myr. This then infers it is a wrong conclusion for me to say the crystalline water ice on Charon is an indicator of when the surface was catastrophically disrupted. That doesn't mean it wasn't catastrophically disrupted, only that using the crystalline structure of the water ice as an age dating method on medium bodies and for this event is an unreliable method. However, the same can not be said about the small satellites. The surface of the small satellites should be amorphous (missing the 1.65 dip) but are not. All this info taken together still strongly suggest recent events placed the small satellites in orbit.
Near-Infrared Spectroscopy of Charon Possible Evidence for Cryovolcanism on KUIPER BELT OBJECTS July 2007
When water ice is warmed to temperatures > 78 K it crystallizes, it only retains its crystalline structure on geologically short timescales (<1 Gyr). Given the typical heliocentric distances of KBOs, it is not possible to achieve such surface temperatures by solar heating alone. In addition to the mystery of how crystalline ice is created, there is the question of how it survives. The e-folding time for the amorphization of crystalline water ice by cosmic rays is about 1.5 Myr (Cooper et al. 2003) down to depths typically probed by infrared observations. Thus crystalline water ice must be replenished on these comparable, geologically short, timescales. In addition, ammonia hydrates are known to be decomposed by cosmic rays (Strazzulla & Palumbo 1998), such that their presence on the surface of an icy moon provides corroborating (although less restrictive) evidence for surface renewal.
I created the below table from info contained in the above paper, it shows larger bodied objects like Pluto can hold onto lighter volatile gasses like methane (CH4). Medium bodied objects like Charon loose their more volatile gasses and tend to exhibit water ices that are crystalline in structure while small bodied objects tend to have water ices that are amorphous (lacking the 1.65 micron dip). Funny thing about Pluto's small satellites, their surfaces are crystalline water ice as they have the 1.65 micron dip, meaning their surfaces were heated to greater than 78 K in the last 1.5 myr. Combine that info with the photo sensitive and photo disassembled NH3 on their surface's and it strongly suggest these are chunks of ice ejected from Charon and/or Pluto.
Some process related to the medium body size's appears to form crystalline ice on times scales less than 1.5 myr. This then infers it is a wrong conclusion for me to say the crystalline water ice on Charon is an indicator of when the surface was catastrophically disrupted. That doesn't mean it wasn't catastrophically disrupted, only that using the crystalline structure of the water ice as an age dating method on medium bodies and for this event is an unreliable method. However, the same can not be said about the small satellites. The surface of the small satellites should be amorphous (missing the 1.65 dip) but are not. All this info taken together still strongly suggest recent events placed the small satellites in orbit.
Another potential scenario to explain crystallized ice is gouging or excavation by impacts. In essence an impactor carves out a hole from which heated ice material is expelled and scattered on the surface converting into a crystallized form. But this would leave large patches of crystallized spots with vast voids between them much like we see with the ammonia and the frequency of impacts is too low for this to explain the crystallized ice.
Solid-state convection is a real possibility at great depths on Charon, where the temperatures exceed 140 K. At the surface of Charon, however, where the temperatures are 50 K, the ice is too viscous by orders of magnitude, and the expansivity too small (even negative) for convection to act there. We therefore conclude that solid-state convection does not bring fresh crystalline ice to
Charon’s surface.
Most papers on the subject tend to be dated pre-New Horizons flyby. Because of this most assume cryovolcanism is the mechanism driving this process. But we now know Charon is dead, on Charon cryovolcanism is ruled out. In addition to Charon we also know 3 of the 4 smaller 6-30 mi satellites have crystallized surfaces along with ammonia hydrates, they too are dead.
A seemingly regular pattern found among 400-800 km radius bodies is that along with having crystallized water ice they also often have ammonia hydrates. Another commonly expressed concept to explain the crystallized ice, is that micrometeorites are heating the surfaces melting the ice quickly forming a crystalline structure. If this were the case there wouldn't be any ammonia hydrates as the ammonia is very volatile and would be evaporated away more vigorously from the micrometeorite impacts than crystallized water would be formed.
Another possible explanation is found in this paper HST/NICMOS spectroscopy of Charon's leading and trailing hemispheres written September 2000 was hypothesizing a concept to explain observed spectroscopic spectral lines from Charon which indicated Charon had ammonia on its leading orbital hemisphere but not on the trailing hemisphere.
The spectra also indicated Charon had crystallized water ice on both the leading and trailing hemispheres. It was hypothesized the nitrogen atmosphere of Pluto was enveloping both planets. The nitrogen (N2) from Pluto's atmosphere was broken down by UV light to become two separate (N)itrogen elements which theoretically recombined with the water ice's (H2O) hydrogen on Charon to make NH3. As they were only able to view Pluto/Charon from ground based telescopes or Hubble in 2000 this seemed like a pretty good synopsis.
The problem for this hypothesis now is that we flew past Charon and can see how ammonia is splattered in blobs around Charon like someone shot paint balls at it. Atmospherically deposited ammonia would be more evenly dispersed. Splatter painted blobs of NH3 primarily on the leading surface would make sense if Pluto were ejecting blobs of NH3 from it's surface during Milankovitch cycles where N2 reaches its triple point. As Charon orbits Pluto, it would rotate into ejected material from Pluto.
Solid-state convection is a real possibility at great depths on Charon, where the temperatures exceed 140 K. At the surface of Charon, however, where the temperatures are 50 K, the ice is too viscous by orders of magnitude, and the expansivity too small (even negative) for convection to act there. We therefore conclude that solid-state convection does not bring fresh crystalline ice to
Charon’s surface.
Most papers on the subject tend to be dated pre-New Horizons flyby. Because of this most assume cryovolcanism is the mechanism driving this process. But we now know Charon is dead, on Charon cryovolcanism is ruled out. In addition to Charon we also know 3 of the 4 smaller 6-30 mi satellites have crystallized surfaces along with ammonia hydrates, they too are dead.
A seemingly regular pattern found among 400-800 km radius bodies is that along with having crystallized water ice they also often have ammonia hydrates. Another commonly expressed concept to explain the crystallized ice, is that micrometeorites are heating the surfaces melting the ice quickly forming a crystalline structure. If this were the case there wouldn't be any ammonia hydrates as the ammonia is very volatile and would be evaporated away more vigorously from the micrometeorite impacts than crystallized water would be formed.
Another possible explanation is found in this paper HST/NICMOS spectroscopy of Charon's leading and trailing hemispheres written September 2000 was hypothesizing a concept to explain observed spectroscopic spectral lines from Charon which indicated Charon had ammonia on its leading orbital hemisphere but not on the trailing hemisphere.
The spectra also indicated Charon had crystallized water ice on both the leading and trailing hemispheres. It was hypothesized the nitrogen atmosphere of Pluto was enveloping both planets. The nitrogen (N2) from Pluto's atmosphere was broken down by UV light to become two separate (N)itrogen elements which theoretically recombined with the water ice's (H2O) hydrogen on Charon to make NH3. As they were only able to view Pluto/Charon from ground based telescopes or Hubble in 2000 this seemed like a pretty good synopsis.
The problem for this hypothesis now is that we flew past Charon and can see how ammonia is splattered in blobs around Charon like someone shot paint balls at it. Atmospherically deposited ammonia would be more evenly dispersed. Splatter painted blobs of NH3 primarily on the leading surface would make sense if Pluto were ejecting blobs of NH3 from it's surface during Milankovitch cycles where N2 reaches its triple point. As Charon orbits Pluto, it would rotate into ejected material from Pluto.
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Quote from Universe Today Article
Astronomers rank an object’s reflectivity by its albedo (al-BEE-do). A body that reflects 100% of the light is said to have an albedo of 1.0. Venus’ albedo is .75 and reflects 75% of the light it receives from the sun, while the darker Earth’s average is 30%. Trees and the darker-toned continents reflect much less light compared to Venus’ pervasive cloud cover. In contrast, the coal-dark moon reflects only 12% of the sunlight falling on it and fresh asphalt just 4% – smack in the middle of the 2-6% range of most known comets. I created this table to demonstrate just how bright Styx, Nix, Kerberos and Hydra are compared to other Plutinos in their neighborhood. Nix and Hydra are about 20% brighter than their parent planet indicating they are younger than the parent planets. All Plutinos are far darker than Pluto and its moons. Normal Plutinos are between 6 and 29 times darker than Pluto's moons. I didn't include 1994 JR1 in the table but its a Plutino with an albedo of .04 in line with other nearby Plutinos. New Horizons' had a dust counter on board but didn't detect any worth mentioning. NASA scientists' have suggested micro meteorites are perpetually cleaning regolith off the surface's of Pluto's moons increasing their albedo's but apparently this same process does not take place with all the other Plutinos in the nearby area only around Pluto. Then when NASA calculates the age of the moons based on impacts they use soft dark regolith not water ice to scale and shift the results. Nix has an albedo of .56 (56% reflected light) and Hydra .83 (83%), indicating they are not covered in regolith making them young, much younger than all other Plutino's. The albedo of Triton is .76 more in line with all the Pluto bodies than all other Plutinos. |
Albedo chart comparing how bright the moons of Pluto are compared to other Plutinos
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Comet 67p a KBO, on the other hand, has a reflectance or albedo of .06 (6%) and is really dark because of all the regolith on its surface it is covered in 8 inches of dark dust or regolith. The below image shows a comparison of how dark comet 67p is relative to Enceladus, Earth and our Moon
It takes time to darken bright ice in space. Sublimation (evaporation) leaves behind the dust particles (regolith) and cosmic radiation bakes the ice darkening it, these processes take time. When objects are observed to have high albedo's (reflectance) they are always considered young unless those objects happen to be Pluto's moons then somehow they are old.
In the abstract of this Jason Cook paper. It says
We calculate the rate at which crystalline water ice is amorphized (Lacking definite form-organization; shapeless; formless of no particular type) by solar UV/visible radiation, finding that at the depths probed by H and K observations (approximately equals 350 micro meters), the e-folding time to amorphize ice is (3-5) x 10,000 years. This implies Charon’s ice crystallized from a melt, or has been heated to >90 K, during the last 100,000 years.
The southern hemisphere of Charon has been shown to be less than 100,000 years old as it was heated to 90K creating a smooth surface within that time frame and is currently 35K. In other words, Charon's warm internal guts spilled onto the surface recently making it smooth.
The many shards of angular debris on the southern hemisphere of Charon infer the recent resurfacing process coincided with an explosive release accompanied by orbital fragments which settled back onto the surface during the cooling process.
Spectral lines of absorption used for identifying ammonia hydrates on Charon were taken at these six observational angles. It seemed to me that while the northern hemisphere is well represented by these angles of observation the southern hemisphere is not as clearly represented. Personally, I am more curious about the southern hemisphere's ammonia content and was wondering if that data was available or able to be separately identified.
In the abstract of this Jason Cook paper. It says
We calculate the rate at which crystalline water ice is amorphized (Lacking definite form-organization; shapeless; formless of no particular type) by solar UV/visible radiation, finding that at the depths probed by H and K observations (approximately equals 350 micro meters), the e-folding time to amorphize ice is (3-5) x 10,000 years. This implies Charon’s ice crystallized from a melt, or has been heated to >90 K, during the last 100,000 years.
The southern hemisphere of Charon has been shown to be less than 100,000 years old as it was heated to 90K creating a smooth surface within that time frame and is currently 35K. In other words, Charon's warm internal guts spilled onto the surface recently making it smooth.
The many shards of angular debris on the southern hemisphere of Charon infer the recent resurfacing process coincided with an explosive release accompanied by orbital fragments which settled back onto the surface during the cooling process.
Spectral lines of absorption used for identifying ammonia hydrates on Charon were taken at these six observational angles. It seemed to me that while the northern hemisphere is well represented by these angles of observation the southern hemisphere is not as clearly represented. Personally, I am more curious about the southern hemisphere's ammonia content and was wondering if that data was available or able to be separately identified.
So, Yesterday April 26th, 2017, I tweeted another question to Jason Cook
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I've seen info released about ammonia on Charon's northern hemisphere but none on the southern. Do you know if it exist there as well?
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Unfortunately no reply from Cook on this question. The paper does indicate it is thought that ammonia exists uniformly across all of Pluto so I will leave it at that.
The significance of this question is that if Pluto is splattering ammonia hydrates onto the moons every 1.4 Myrs and the southern hemisphere of Charon doesn't have any NH3 then it is confirmation Charon's southern surface is younger than 800 thousand years (last time Milankovitch cycle set N2 at triple point) which is in line with Jason's paper which claims it was heated and smoothed (crystallized) within the last 100 thousand years. This would then mean Charon exploded very recently and these small satellites are likely young bodies not old bodies simply covered with young material. This would further support the concept some of them are fragments from Charon. This would also demonstrate that circular orbits could be imposed upon small bodies relatively quickly.
It would also be nice to be able to know the ratio of NH3 on Charon compared to the small satellites as this would indicate similar or dissimilar ages. If the small satellites came from the southern hemisphere of Charon the ratio of NH3 should match that of the northern hemisphere. If the north hemisphere of Charon and the small satellites are the same age then the small moons were likely placed in orbit by the explosive ejection of Charon's crust and this event would have occurred very recently.
But if the southern hemisphere of Charon has no ammonia while the northern does or the ratio of the ammonia found on the small satellites matches that on the northern hemisphere of Charon then the small satellites themselves are likely very young as are their surface's.
Good news Alan Stern and team are now in talks about sending an orbiter to Pluto Perhaps we will get more detailed data about ammonia on the next trip.
Below in purple are excerpts from a paper called
Measuring temperature and ammonia hydrate ice on Charon in 2015 from Keck/OSIRIS spectra
I'll refer to it as the NH3 paper.
NH3 paper page 18-19
The presence of ammonia on Charon is unexpected at first given that a majority of ammonia in the upper ice layers should be destroyed within 20 Myr in a 1 eV-10 GeV proton radiation environment (Cooper et al., 2003; Cook et al., 2007). For crystalline water ice, radiation breaks and reforms the bonds between molecules, thus converting water ice from the crystalline to the amorphous (Lacking definite form-organization; shapeless; formless) phase. For ammonia ice, the individual molecules are dissociated by radiation and cosmic rays, not undergoing a phase conversion.
Photodissociation of ammonia (NH3) takes 20 million years and converting crystalline water ice via radiation to its amorphous phase takes 1.5 million years. Both the ammonia and crystalline water ice indicate some young processes have taken place recently.
NH3 paper page 3
The e-folding time for crystalline water ice to be converted to amorphous water ice in a radiation environment of 1 eV-10 GeV protons, without considering recrystallization processes, is 1.5 Myr; this is down to the depth probed by near-infrared H and K band observations (Cook et al., 2007).
NH3 paper page 17
In terms of longitudinal coverage, our results complement the ammonia distribution from New Horizons (Dalle Ore et al., 2016; Grundy et al., 2016), and together they suggest that ammonia is uniformly distributed across the surface of Charon.
Astronomy Now produced an article about Pluto on Dec 20, 2015, five months after the fly by. At that time this is what scientists were saying about the ammonia on Charon's surface.
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The informally named Organa Crater, had been noted as being especially rich in NH3. It’s not yet known what controls the distribution of Charon’s NH3, or if it comes from Charon’s interior or an external source.
NH3 paper page 19 - This is the paper's two delivery concepts for ammonia - it's either pushed up from below or dropped down from above.
Some process is likely renewing ammonia in the surface layers by drawing on a reservoir that is protected from radiation and cosmic rays. Ammonia on Charon's surface in the present day can be explained by the slow diffusion rate through the upper layers of water ice and by impact gardening....The ammonia may be primordial, contained in the progenitor (direct ancestor) bodies that collided to form Pluto and Charon (Canup, 2011)
The significance of this question is that if Pluto is splattering ammonia hydrates onto the moons every 1.4 Myrs and the southern hemisphere of Charon doesn't have any NH3 then it is confirmation Charon's southern surface is younger than 800 thousand years (last time Milankovitch cycle set N2 at triple point) which is in line with Jason's paper which claims it was heated and smoothed (crystallized) within the last 100 thousand years. This would then mean Charon exploded very recently and these small satellites are likely young bodies not old bodies simply covered with young material. This would further support the concept some of them are fragments from Charon. This would also demonstrate that circular orbits could be imposed upon small bodies relatively quickly.
It would also be nice to be able to know the ratio of NH3 on Charon compared to the small satellites as this would indicate similar or dissimilar ages. If the small satellites came from the southern hemisphere of Charon the ratio of NH3 should match that of the northern hemisphere. If the north hemisphere of Charon and the small satellites are the same age then the small moons were likely placed in orbit by the explosive ejection of Charon's crust and this event would have occurred very recently.
But if the southern hemisphere of Charon has no ammonia while the northern does or the ratio of the ammonia found on the small satellites matches that on the northern hemisphere of Charon then the small satellites themselves are likely very young as are their surface's.
Good news Alan Stern and team are now in talks about sending an orbiter to Pluto Perhaps we will get more detailed data about ammonia on the next trip.
Below in purple are excerpts from a paper called
Measuring temperature and ammonia hydrate ice on Charon in 2015 from Keck/OSIRIS spectra
I'll refer to it as the NH3 paper.
NH3 paper page 18-19
The presence of ammonia on Charon is unexpected at first given that a majority of ammonia in the upper ice layers should be destroyed within 20 Myr in a 1 eV-10 GeV proton radiation environment (Cooper et al., 2003; Cook et al., 2007). For crystalline water ice, radiation breaks and reforms the bonds between molecules, thus converting water ice from the crystalline to the amorphous (Lacking definite form-organization; shapeless; formless) phase. For ammonia ice, the individual molecules are dissociated by radiation and cosmic rays, not undergoing a phase conversion.
Photodissociation of ammonia (NH3) takes 20 million years and converting crystalline water ice via radiation to its amorphous phase takes 1.5 million years. Both the ammonia and crystalline water ice indicate some young processes have taken place recently.
NH3 paper page 3
The e-folding time for crystalline water ice to be converted to amorphous water ice in a radiation environment of 1 eV-10 GeV protons, without considering recrystallization processes, is 1.5 Myr; this is down to the depth probed by near-infrared H and K band observations (Cook et al., 2007).
NH3 paper page 17
In terms of longitudinal coverage, our results complement the ammonia distribution from New Horizons (Dalle Ore et al., 2016; Grundy et al., 2016), and together they suggest that ammonia is uniformly distributed across the surface of Charon.
Astronomy Now produced an article about Pluto on Dec 20, 2015, five months after the fly by. At that time this is what scientists were saying about the ammonia on Charon's surface.
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The informally named Organa Crater, had been noted as being especially rich in NH3. It’s not yet known what controls the distribution of Charon’s NH3, or if it comes from Charon’s interior or an external source.
NH3 paper page 19 - This is the paper's two delivery concepts for ammonia - it's either pushed up from below or dropped down from above.
Some process is likely renewing ammonia in the surface layers by drawing on a reservoir that is protected from radiation and cosmic rays. Ammonia on Charon's surface in the present day can be explained by the slow diffusion rate through the upper layers of water ice and by impact gardening....The ammonia may be primordial, contained in the progenitor (direct ancestor) bodies that collided to form Pluto and Charon (Canup, 2011)
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The NH3 paper refers to the impact at Organa crater on Charon and suggest that either the ammonia is below the surface and gouged out by impactors (their preferred explanation) or is delivered from above by the impactor itself.
Consider the logic of this. Two impacts about 75 miles apart show completely different splatter patterns even though the paper says the ammonia is uniformly distributed across the surface of Charon via slow diffusion through the upper layers of ice. This image clearly shows that the ammonia is delivered by the impactor. |
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If ammonia was uniformly welling up from below the surface then both impacts would have gouged out ammonia. The strongest degree of ammonia is in the central area of the Organa crater again supporting the idea it was delivered by the impacting body.
The difficulty for scientists in describing this scene becomes, where does all this ammonia come from if not from below? I'm saying it's coming from Pluto when it's temperature and pressure is at nitrogen's triple point, they simply have not conceived of this idea yet so, it must be, in their eye's coming from below the surface.
Organa crater is clearly a chunk of Pluto that got ejected and hit Charon splattering ammonia and other volatile gasses which have since evaporated away. Take note of all the freckle speckles of splatter patterns where other blobs of soft Pluto ices hit Charon. If the material was exposed from below the surface during an impact you would see it as narrow streaks. Take note of the white streaks (exposed white ice from the impact) this is the bright surface exposed below the dusty surface. These streaks should be green not white if the ammonia is being exposed from below the surface. Instead you see blobs that follow the patterns of the streaks but lay on top in circular blotches.
Not convinced? Consider this!
The difficulty for scientists in describing this scene becomes, where does all this ammonia come from if not from below? I'm saying it's coming from Pluto when it's temperature and pressure is at nitrogen's triple point, they simply have not conceived of this idea yet so, it must be, in their eye's coming from below the surface.
Organa crater is clearly a chunk of Pluto that got ejected and hit Charon splattering ammonia and other volatile gasses which have since evaporated away. Take note of all the freckle speckles of splatter patterns where other blobs of soft Pluto ices hit Charon. If the material was exposed from below the surface during an impact you would see it as narrow streaks. Take note of the white streaks (exposed white ice from the impact) this is the bright surface exposed below the dusty surface. These streaks should be green not white if the ammonia is being exposed from below the surface. Instead you see blobs that follow the patterns of the streaks but lay on top in circular blotches.
Not convinced? Consider this!
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It is entirely possible all the sublimation pits on the surface of Sputnik Planitia are the remnants of ejected nitrogen paint balls fired into space during a time 0.8 mya when Pluto's atmospheric pressure was high enough for nitrogen to reach its explosive triple point. |
The suggestion by this NH3 paper is that subsurface pressures are pushing ammonia up from below squeezing it onto or near the surface then random impacts reveal the ammonia. I might be able to accept this concept if it weren't for the small satellites which are also covered in ammonia. The small moons don't have any internal pressure pushing ammonia to their surface's instead the ammonia is being placed onto the surface from above and recently or else the small satellites themselves are recently emplaced. If the small moons are coated in NH3 like Charon then the source of the ammonia is from outside not inside as there are no internal pressures pushing outward on the small moons. The small moons have to be coated from the outside inferring the same process is taking place on Charon.
Pluto reaching triple point pressures and temperatures of N2 and exploding gasses and ices is the only reasonable way to explain all these bodies being covered in ammonia. This does not negate the idea the moons themselves could be young just that the surface NH3 is expelled from Pluto. Since both Charon's old northern hemisphere and the small moons have ammonia and the ammonia is not squeezed up from below Charon's surface, Pluto must be splattering and spray painting the ammonia onto the surface of Charon when N2 reaches its triple point. Nix's red tholin impact shows that not only are volatile and NH3 ices ejected from Pluto but chunks of red tholin covered water ice is as well.
NH3 paper page 14
The presence of crystalline water ice on Charon is not in doubt since the 1.65 micrometer band, unique to the crystalline phase, is clearly detected in spectra. What is less obvious is the reason why crystalline water ice is present at all, not to mention that it is present in such large quantities (about 90%; Cook et al., 2007; Merlin et al., 2010). Conversion of water ice from the crystalline phase to the amorphous phase should take 1.5 Myr (Cooper et al., 2003), assuming a radiation environment of 1 eV-10 GeV protons and no recrystallization processes.
NH3 paper page 20
The placement of crystalline water ice on the surface of Charon likely occurred 4 Gyr ago (Moore et al., 2016), meaning that equilibrium was reached over 3.5 Gyr ago. We do not believe that cryovolcanism is necessary to explain the presence of crystalline water ice on the surface of Charon.
Pluto reaching triple point pressures and temperatures of N2 and exploding gasses and ices is the only reasonable way to explain all these bodies being covered in ammonia. This does not negate the idea the moons themselves could be young just that the surface NH3 is expelled from Pluto. Since both Charon's old northern hemisphere and the small moons have ammonia and the ammonia is not squeezed up from below Charon's surface, Pluto must be splattering and spray painting the ammonia onto the surface of Charon when N2 reaches its triple point. Nix's red tholin impact shows that not only are volatile and NH3 ices ejected from Pluto but chunks of red tholin covered water ice is as well.
NH3 paper page 14
The presence of crystalline water ice on Charon is not in doubt since the 1.65 micrometer band, unique to the crystalline phase, is clearly detected in spectra. What is less obvious is the reason why crystalline water ice is present at all, not to mention that it is present in such large quantities (about 90%; Cook et al., 2007; Merlin et al., 2010). Conversion of water ice from the crystalline phase to the amorphous phase should take 1.5 Myr (Cooper et al., 2003), assuming a radiation environment of 1 eV-10 GeV protons and no recrystallization processes.
NH3 paper page 20
The placement of crystalline water ice on the surface of Charon likely occurred 4 Gyr ago (Moore et al., 2016), meaning that equilibrium was reached over 3.5 Gyr ago. We do not believe that cryovolcanism is necessary to explain the presence of crystalline water ice on the surface of Charon.
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For all their efforts to be accurate and precise, when I read scientific papers, I find there are, at times, points around which consistent logical explanations fail.
There are several processes taking place indicating short time frames, water ice has not been converted from a crystalline structure to an amorphous phase which should have taken place within 1.5 million years of Charon's formation 3.5 to 4 billion years ago. Ammonia hydrates exist and would be disassembled by the sun in 20 million years. The moons have ridiculous spins and pole wobbles. The albedo of the entire system is too bright and screams we are young and coated in young ammonia material. |
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NH3 paper page 21
The presence of ammonia ice everywhere on Charon's surface requires a means of replenishment since it is dissociated on 20 Myr timescales (Cooper et al., 2003; Cook et al., 2007). Ammonia was likely a primordial component of the progenitor bodies that collided to form Pluto and Charon, (complete assumption) and may have played a role in the global cryovolcanic episode 4 Gyr ago (Moore et al., 2016). Since that time, ammonia has been slowly diffusing its way through the thick overlying layer of water ice and may occasionally be brought to the surface in larger quantities by impacts. This explains the presence of hydrated ammonia and its ubiquity across the surface.
It appears impossible for main stream science to accept that processes around Pluto could be recent rather all information presented imply this system is 4 or more billion years old and no matter how much evidence to the contrary they are going to force that concept onto this scene. It appears to me there is more evidence indicating recent processes are taking place than there is supporting old aged processes. Don't misunderstand, I think Pluto itself, Charon and Triton are old but many processes we see occurring around them are recent. Rather than work forward from a distant theoretical 4 Gyr point we should work backward from current observational evidence.
Today I sent another question to Jason,
hope I'm not annoying him.
The presence of ammonia ice everywhere on Charon's surface requires a means of replenishment since it is dissociated on 20 Myr timescales (Cooper et al., 2003; Cook et al., 2007). Ammonia was likely a primordial component of the progenitor bodies that collided to form Pluto and Charon, (complete assumption) and may have played a role in the global cryovolcanic episode 4 Gyr ago (Moore et al., 2016). Since that time, ammonia has been slowly diffusing its way through the thick overlying layer of water ice and may occasionally be brought to the surface in larger quantities by impacts. This explains the presence of hydrated ammonia and its ubiquity across the surface.
It appears impossible for main stream science to accept that processes around Pluto could be recent rather all information presented imply this system is 4 or more billion years old and no matter how much evidence to the contrary they are going to force that concept onto this scene. It appears to me there is more evidence indicating recent processes are taking place than there is supporting old aged processes. Don't misunderstand, I think Pluto itself, Charon and Triton are old but many processes we see occurring around them are recent. Rather than work forward from a distant theoretical 4 Gyr point we should work backward from current observational evidence.
Today I sent another question to Jason,
hope I'm not annoying him.
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Also wondering. Do you know of any work (paper's) identifying ratio of NH3 on small sats vs Charon to compare ages by rate of dissociation?
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Sorry, I don't.
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Unfortunately there seems, currently, to be no way to know if the small moon's surface ammonia is similarly aged to that of the ammonia on Charon. But its presence on all the moons indicate it is an external process that is taking place on a short time scale.
If its possible the moons are being splattered with ammonia from Pluto then it is also possible and probable that chunks of H2O are also being ejected off Pluto. The red tholin zit on Nix indicates this process is taking place suggesting that Nix is also a chunk of Pluto but how old? Since the moons are dead and much much brighter than any other dead Plutino in the area this along with the ammonia supports the concept they are young, nearly as young as the surface of Sputnik Planitia and Charon's southern hemisphere as their albedos are very closely matched to these surfaces.
If I knew whether or not the southern hemisphere of Charon had ammonia I could narrow it's explosion down to within 100,000 years but I can't. The best I can say is that these processes creating moons and ammonia splatter are occurring in multiples of 1.4 Myrs and are certainly less than 20 million. Charon could have violently popped its cork within 100,000 years placing Hydra into orbit or it could have happened as long ago as 1.5 million years based on the crystalline ice. I am fairly comfortable saying Pluto and Charon may be old but the small moons, the ammonia hydrates, Sputnik Planitia, Tombaugh Regio and Charon's southern hemisphere are not.
Just a little sompin sumpin for nutin.
If its possible the moons are being splattered with ammonia from Pluto then it is also possible and probable that chunks of H2O are also being ejected off Pluto. The red tholin zit on Nix indicates this process is taking place suggesting that Nix is also a chunk of Pluto but how old? Since the moons are dead and much much brighter than any other dead Plutino in the area this along with the ammonia supports the concept they are young, nearly as young as the surface of Sputnik Planitia and Charon's southern hemisphere as their albedos are very closely matched to these surfaces.
If I knew whether or not the southern hemisphere of Charon had ammonia I could narrow it's explosion down to within 100,000 years but I can't. The best I can say is that these processes creating moons and ammonia splatter are occurring in multiples of 1.4 Myrs and are certainly less than 20 million. Charon could have violently popped its cork within 100,000 years placing Hydra into orbit or it could have happened as long ago as 1.5 million years based on the crystalline ice. I am fairly comfortable saying Pluto and Charon may be old but the small moons, the ammonia hydrates, Sputnik Planitia, Tombaugh Regio and Charon's southern hemisphere are not.
Just a little sompin sumpin for nutin.
