Drifter

If you look at current thinking on Hyperion … see Wikipedia: https://en.wikipedia.org/wiki/Hyperion_(moon) … it’s a bit surprising nobody openly appears to be proposing this is a dead captured comet whose final fragmentational demise was halted by the gravitational embrace of Saturn? If you look at this NASA website that gives a rotational view of this wobbly object given extra instability by the proximal orbit of Titan: https://solarsystem.nasa.gov/moons/saturn-moons/hyperion/in-depth/ …. as you enlarge and spin the digital image around, then screenshot … it’s evident there may be a blunt-nosed head to this ‘moon’ with ‘wicking’ marks along the sides: Phobos (although of different composition suggesting an asteroid) shows a similar serious indentation and striations along it’s body in alignment with the direction of the Stickney crater impact. https://en.wikipedia.org/wiki/Phobos_(moon) Heat/velocity induced ‘wicking striations’ are better illustrated on the surface coma of 67P/Churyumov-Gerasimenko: …. probably created largely by a series of moderately toasty close encounter fly-bys of the Sun? In summary, it seems logical to imagine Hyperion as a ‘snowball’ of compacted ice/rock debris being smashed out of it’s cushy idyll nestling in the icy regions of the Kyper/Asteroid Belt - impelled on a trajectory - a close encounter with our Sun - it’s impacted rear ‘hollowed out’ further by cratering/flaking in a series of mini pock-marked explosions of ice/dust debris flying off the back end when the heat generated in solar transit reached critical point to create trapped gas/steam blow outs - eventually making Hyperion look like a piece of coral. Fair to say most of these craters in the first image don’t look much like impacts … more like ‘blow-outs’, … no? You see similar blow-out marks on the surface of some meteorites of certain composition (particularly iron) that have penetrated and ignited in Earth’s atmosphere. Other examples of pitting/striation marks on a smaller scale: Just thought I’d sound out others on here who might have a similar impression about Hyperion.

Just a thought … could there be an instant - as huge worlds are stripped away from their lower gravity orbits around passing stars (whose momentum prevents the star itself being sucked in and destroyed in the black hole) - where the worlds and their moons are being torn apart and vaporised before full transition through the Event Horizon … it makes sense that fleeting flashes of light could escape the periphery as Craney hinted … just before ‘full consumption’??🤔 This article seems to dispel the notion EVERYTHING is swallowed in, destroyed and can’t escape from a black hole. https://scitechdaily.com/black-holes-have-tantrums-and-scientists-have-finally-captured-the-gamma-rays-from-such-ultra-fast-outflows/

If people are concerned about the possible amounts of water that were likely generated on our Moon to create such rilles this article should reassure them that water generated by volcanism is not only sufficient in lunar scenarios but is sufficient to completely dispel the rather dodgy notion Earth’s water arrived from the asteroid belt! 🤔 https://courses.lumenlearning.com/geo/chapter/reading-volcanic-gases-pyroclastic-flow-and-tephra/ As you notice in the chart … water vapour is the most abundant gas created by this liquifying volcanic process. [Sublimation doesn’t happen much to our planet … so however much the ice caps melt … my advice in the long term is … move to/ and build on higher ground! …😄 ]

Most odd … a reply I dropped earlier in answer to Craney seems to have been removed? … it basically said: If the material was gravitationally stripped debris harvested from stellar near misses wouldn’t we see a sustained ‘burn’ event rather than large super explosions suggesting planets/stars/moons/dark matter of some sort being consumed? Would love to have had a ring-side seat to that event! V. spectacular. I respect your explanations … but wonder if the first would produce enough material for the dramatic ‘explosion’ events observed? I considered the second idea … objects lensing from behind the BH but saw the tight bunching of these events and therefore didn’t think it applied in this case. If you can source better quality video footage to support that … or observations of other BH doing the same … I’m always open to being convinced. Guess there won’t be any radiation data supporting planets being stripped from these stars and trashed? Btw, wise not to be restricted by ‘definitions’ or currently known ‘laws of physics’ that shift radically each decade … and possibly with each fresh observation! …. I hope the Moderators on here are open to members challenging ‘Establishment Theory’ with good evidence? …

If you look carefully at the sequence showing only 6 months activity … it’s interesting to see 4 possibly 5+ flashes of light emitting from the epicentre region of this black hole. Doesn’t this suggest light can escape the Event Horizon as possibly smaller stars or dark matter we can’t see are being sucked in and destroyed?

I just want to drop a couple more indicators that suggest this labyrinthine view of the upper crust of the Moon might be true …where surface volcanism has probably created vast tracts where gas and lava under pressure have cut chambers that have cooled later and ‘honeycombed’ the subsurface. From this synopsis of the Moon ( https://en.wikipedia.org/wiki/Moon ) Under the section Surface Geology: “The discovery of fault scarp cliffs suggest that the Moon has shrunk by about 90 metres (309ft) within the past billion years. Similar shrinkage features exist on Mercury. Mare Frigoris, a basin near the north pole long assumed to be geologically dead, has cracked and shifted. Since the Moon doesn’t have tectonic plates, it’s tectonic activity is slow and cracks develop as it loses heat” Meteor impacts over the years fracturing chambers full of condensate will also create this shrinkage as tidal locking bakes the surface layers driving water vapour sublimation out through porous deposits and tenuous atmosphere as it shimmers refractions evaporating into Space. Other views why it is shrinking: https://www.discovermagazine.com/the-sciences/the-moon-is-shrinking Worth adding is that these shrinkage marks are relatively recent tying in with data suggesting volcanism faded recently and therefore rille formation followed later as impacts and heave triggered ooze events. Another reason why most rille channels in the Solar System are free of dust and volcanic(molten lava) debris. Looking at the info on the history of the lunar iron core … I can imagine as the core of the Moon cooled, similar honeycombed chambers would be created much deeper below the surface in the molten iron layers … also explaining why the Moon has a much lower density than the Earth … even though it shares a very similar isotopic signature that suggests both bodies were created at the same time birthed from star matter and evolved along very similar paths ‘married’ together along similar celestial orbits that influenced their geological similarities. A Honeycomb Moon Theory also ties in nicely with the recording of vibration and resonance …. the sonic ringing event that the Moon makes when it is struck by large impactors or explosions detonated on it’s surface. https://sagame.damnxd.org/does-moon-sound-like-bell/ Not hollow moon theory … just more logical honeycombed moon theory.

Many apologies UK Diver … I thought you were publicising something you had organised. I have no links to the Space Centre or a means to determine exactly which personnel channels to go through in that organisation to make this sort of complaint effective. Maybe you or someone one else on here reading this with those necessary links, could pass on the concern of a few members on here about using platforms for science talks that sift the Public’s data and record their surfing habits even when they don’t have these websites/Apps open. Facebook is making £€$billions from these activities that are intrusive to many … pushing marketing and spam … much of it ruining one’s surfing experience on the Internet.

I used the term ‘super volcano’ to describe a large area eruption crater filled with a lava lake …. maybe I used the wrong term here? … I avoided calling them calderas because I didn’t feel these H+P features showed evidence of a ‘collapse’ in the terrain. Interesting you mentioned these as low gravity/low explosive events very different to something like Olympus Mons …. this fits in very nicely to what I was thinking and the observation here … large very old volcanoes with low lip edges simmering away gently before eventually dying and the lips weathering slightly. I agree with your summary the rilles formed much later … but find it hard to believe these rilles are collapsed lava tubes? …. because what are the chances that nearly every rille in the Solar System collapsed evenly along it’s whole length to reveal an uninterrupted smooth channel? (Just want to clarify - I wasn’t stating in my OP that lava tubes were formed by water …. just the idea water condensate would collect in old cooling subsurface chambers created by trapped gas and lava - as these giant eruptions faded away) I feel it ties in quite neatly that meteor impacts surrounding these large flattish craters could happily puncture these pressurised chambers and create ‘ooze’ events … like we see in the Yellowstone Park caldera(not inferring Old Faithful was triggered by a meteor impact btw!). It’s likely these ‘ooze’ events could sustained erosion from substantial condensate production over millions of years …. creating either surface erosion … or possibly the cutting of subsurface channels(resistant to sublimation) that could dissolve the underlying ejecta and leave a smooth collapsed river-like feature with an evaporation point at the end. Nearly all rilles give the inescapable nagging impression of being created by a very mobile liquid that has evaporated at the end over a considerable distance. Lava rarely ever creates that effect …. disappearing completely without trace?!🤔 As recent research has shown lunar volcanism mechanisms and molten core activity lasting much longer than initially thought … we finally have an exciting scenario (along with lunar tremor data) for establishing the Moon once had a substantial atmosphere and at least agreeable conditions for ‘ooze’ erosion. It’s a compelling notion which could really open up exciting new avenues of research of our nearest neighbour … and widen options on where we can establish Moon Bases in future …. We won’t be tied to the ice deposits in lakes around the Poles … but possibly we could tap into the fresh mini ooze channel in Schroter's Valley instead? - if the ‘source’ is still delivering?😁👍 If it’s true rille formation around meteor impacts shows water and not lava sources close to the surface near ancient eruptions … this discovery could seriously cut down on the amount of drilling equipment we would need to cart to the Moon to sustain research colonies there. It remains to be seen what levels of purification will be required for the water extracted from these subsurface reservoirs.

Here’s a thought … If you cast an eye over this photo … …. several rilles emerge from the eye of small impact disturbances around the periphery of Prinz and Herodotus craters. If you are of the school of thought rille channels are either created by lava or water … maybe this is suggesting that both Herodotus and Prinz are ancient supervolcano craters rather than impacts? Imagine the many labyrinthine periphery chambers of lava tubes and gas caverns created under pressure trying to reach the surface and break through the hardened lunar crust around the main vent of a supervolcano …. and you can see why some of these meteor impacts around both H and P have triggered the creation of these small rilles puncturing leakage from these chambers. Note Vera, Ivan, Aristarchus B and Herodotus B impacts triggering rille production in the image above. Vera and Ivan shown in close-up below: Considering H and P filled with smoothed lava-lake crusts around the time of their demise - maybe the rilles around the periphery formed later when ash/pummice dust ejecta had long since ceased? …. because rille channels are mostly clear of dust, ash and molten material. It’s worth noting there is never much trace of built-up of lumpy lava deposits along the edges of any rilles in our Solar System … nor at the very end of these channels where most cooling has occured often miles from the ‘source’. I’ll leave members who are drawn more to lava creating rilles - to draw their own conclusions on that serious ‘anomaly’. We see this pattern of events on most major bodies in our Solar System that has a history of volcanism … I like the idea of a network of subsurface labyrinths around the main emission vent of these giant volcanoes. Some of these enclosed chambers must eventually fill with liquid condensates as volcanoes die - water being a bi-product of the liquefaction of rock that allows lava to flow - here it eventually gets trapped in these enclosed chambers largely immune from sublimation. Some subterranean reservoirs on Earth get utilised by bottled water industries as a healthy tonic! Let’s hope the Moon has drinkable varieties to sustain longterm Moon Base projects. [Hoping they make the first permanent Moon base near the incredibly interesting Schroter's Valley v. soon] We now know there is a building concensus that volcanism on the Moon(and hence a very active magnetic core flux) was evident around the time dinosaurs roamed the Earth: https://earthsky.org/space/moon-saw-volcanic-eruptions-in-geologically-recent-times/ This new timeline for lunar history suggests this magnetic flux was strong enough to create a thick protective atmosphere for much longer than first imagined - thus reducing the effects of extreme sublimation of liquids and gases generated by v. lively volcanism. Interesting to conclude our Moon might have still had a significant atmosphere as little as only 18 million years ago … considering the thin atmosphere we see today during the transition extremes of v. long lunar day/night … who is to say there might not have been ample time for water ooze erosion? … maybe even weather systems on the Moon at some point in it’s history? An exciting prospect that might explain some particulate weathering on it’s surface and the formation of ‘dunes’ the lunar buggy bounced over during recent explorations of the surface. I realise it is a ‘big ask’ to get members to consider the outrageous idea that the huge Aristarcus meteor impact fractured multiple chambers of condensate for kilometres around the Herodotus ‘volcano’ - then a much smaller impact Herodotus B triggered a mammoth ooze event creating the erosion of Schroter’s Valley(SV). Yes, it’s an enormous feature that probably needs millions of years of erosion - but it’s displacing light dusty pumice, ash and other ejecta … not cutting through rock like the Colorado River had to do to form the Grand Canyon … so no point using that as a timeline comparison - conditions on the Moon have been very different to that …. and changing rapidly as new discoveries are made. I understand why most astronomers seem to believe these rilles are only formed by lava … not water - but lets not get bogged down by that argument here … first things first …. it is immaterial to the strong evidence that many rilles tend to surround features that are almost certainly ‘volcanic’ in origin - or come from impact disturbance around areas that were very volcanic at one time. Hence the main point of this post … surely the need for astronomers to step up to the plate with confidence and relabel Herodotus and Prinz as “long dead volcano craters” and not “impacts”?

I have opted out of Facebook because of the spyware/marketing trackers on that platform … and because of the censorship now employed by the owner of that platform. Why are you supporting and funding this place by only hosting your talks on Facebook? … please switch future talks to Zoom or some other non-intrusive platform in future. If you believe in Free Speech and respect people’s right to privacy … you shouldn’t be using Facebook!

Digging further on high albedo lunar impacts … this popped up. https://geology.com/articles/popigai-crater-diamonds/ Diamonds found at the centre of nuclear test explosions on Earth and at the Nordlinger Reis meteor impact site suggest explosions of high intensity can spread tektites and other ‘glass-frozen’ elements thousands of kms … as seen with NR (tektites in Croatia) and with Tycho with debris scattered 5,000 km …. if certain elements are present - graphite is mentioned being present in some meteors .… if the case for pockets of water being locked as condensate in lava tubes around dead lunar volcanoes - as detected by ground penetrating radar recently - it makes sense that there would be a sufficient catalyst here to fuel the immense Tycho surface impact explosion and scatter pattern Here is another compound with high reflectance (TiO2) mentioned in the study B F-G dropped earlier. http://www.psrd.hawaii.edu/Sept04/LunarRays.html#data TiO2 has interesting characteristics(from Wikipedia) Titanium dioxide occurs in nature as the minerals rutile and anatase. Additionally two high-pressure forms are known minerals: a monoclinic baddeleyite-like form known as akaogiite, and the other is an orthorhombic α-PbO2-like form known as brookite, both of which can be found at the Ries crater in Bavaria. It is mainly sourced from ilmenite ore. This is the most widespread form of titanium dioxide-bearing ore around the world. Rutile is the next most abundant and contains around 98% titanium dioxide in the ore. The metastable anatase and brookite phases convert irreversibly to the equilibrium rutile phase upon heating above temperatures in the range 600–800 °C (1,110–1,470 °F) Titanium dioxide (B) is found as a mineral in magmatic rocks and hydrothermal veins, as well as weathering rims on perovskite. TiO2 also forms lamellae in other minerals. Titanium dioxide is the most widely used white pigment because of its brightness and very high refractive index, in which it is surpassed only by a few other materials (see list of indices of refraction). Titanium dioxide crystal size is ideally around 220 nm (measured by electron microscope) to optimize the maximum reflection of visible light. However, abnormal grain growth is often observed in titanium dioxide, particularly in its rutile phase. The occurrence of abnormal grain growth brings about a deviation of a small number of crystallites from the mean crystal size and modifies the physical behaviour of TiO2. The optical properties of the finished pigment are highly sensitive to purity. As little as a few parts per million (ppm) of certain metals (Cr, V, Cu, Fe, Nb) can disturb the crystal lattice so much that the effect can be detected in quality control. It is often referred to offhandedly as "brilliant white", "the perfect white", "the whitest white", or other similar terms. Opacity is improved by optimal sizing of the titanium dioxide particles.

This might point to why there is a problem with the data: https://www.nasa.gov/feature/goddard/2021/as-nasa-s-voyager-1-surveys-interstellar-space-its-density-measurements-are-making-waves This extract: “When one pictures the stuff between the stars – astronomers call it the “interstellar medium,” a spread-out soup of particles and radiation – one might imagine a calm, silent, serene environment. That would be a mistake. “I have used the phrase ‘the quiescent interstellar medium’ – but you can find lots of places that are not particularly quiescent,” said Jim Cordes, space physicist at Cornell and co-author of the paper. Like the ocean, the interstellar medium is full of turbulent waves. The largest come from our galaxy’s rotation, as space smears against itself and sets forth undulations tens of light-years across. Smaller (though still gigantic) waves rush from supernova blasts, stretching billions of miles from crest to crest. The smallest ripples are usually from our own Sun, as solar eruptions send shockwaves through space that permeate our heliosphere’s lining. These crashing waves reveal clues about the density of the interstellar medium – a value that affects our understanding of the shape of our heliosphere, how stars form, and even our own location in the galaxy. As these waves reverberate through space, they vibrate the electrons around them, which ring out at characteristic frequencies depending on how crammed together they are. The higher the pitch of that ringing, the higher the electron density. Voyager 1’s Plasma Wave Subsystem – which includes two “bunny ear” antennas sticking out 30 feet (10 meters) behind the spacecraft – was designed to hear that ringing.”

Personally for me, an example like the double doughnut-ringed Hesiodus A could likely, and most easily, be formed from a rapid double impact in loose thick dusty fine ash deposits scattered around the fringes of ancient Mare and old craters. As for the smoothened features, I can imagine a time when surface volcanism was dying out there would still have been a degree of an atmosphere on the Moon creating winds to happily sculpt the rounded edges of this feature. Later double impacts in a more dried-out crustier, slightly more weathered shrinking Moon, maybe didn’t encourage the formation of the ‘ancient Celtic double-enclave fort effect’ in certain locations where deposits were thin on the ground.😋

Quite like Tiny Clanger(Heather’s) ‘fragments of lunar column basalt’ idea … broken off initially by a deep impact in volcanic substrata? … then thrown up amongst loose debris, both larger pieces at a slight angle disturbed by a second impact … you can see evidence of this in the slight hint of a butterfly profile in the shape of Paracelsus C’s crater …. and the lumpy piles of surrounding ejecta and smoothed edges of the crater lip suggesting a multi-strike scenario? …. One other option … again a two-strike scenario … those angular boulders being fragments of 1st meteor thrown up amongst ejecta of a second angular strike? ….. fragments resistant to crumbling having been formed and tempered “in fire” elsewhere and en route to the lunar surface! Looking at the shadow contours expanded slightly, it appears the rocks are fairly irregular compared to Earth’s ‘column’ examples generally formed in wetter conditions … but they still look a little unusual in a lunar context. Guessing variations in rock strength might occur when basalts are being formed under conditions of differing rates of lunar sublimation (drying and rapid/slow cooling) during the day/night lunar cycle? - likely also affected by the Moon’s magnetosphere strength/molten core activity at that time - which must have formed a semi-protective moisture-trapped atmosphere during some periods of lunar history when some basalts were formed. (The moisture being a high volume bi-product coming from the liquefaction of the rock).

It’s interesting to try and gauge which types of impacts are going to create the most devastating effects … especially impacts hitting a densely populated Earth. Looking at this chart, Tunguska and Chelyabinsk are so insignificant in the big picture, (a tiny red cross on this chart) …their traces soon wiped off the face of the Earth. It would be good if this chart has been updated to show graphically which impacts link to which specific major extinction events … what knocked down the first brick in the domino effect of species collapse (something we are beginning to see today) … the key to the slow lingering demise of many dinosaur species(not just Chicxulub?), the Eocene-Oligocene extinction(not just Popigai?) and Middle Miocene extinction(not just Nördlinger Ries/Steinheim binary asteroid hit?). I guess many ocean asteroid hit’s have left few traces that raised sea temperatures, killed coral and dependent species - many hits are yet to be logged - the data locked in seabed core samples from around the World still needing to be interpreted🤔 … as evidence left may be pretty different to the tektite traces of land impacts? Logging prevailing winds/direction of scatter influenced by Earth’s global weather system flow at that time in History .. the affects of magnetosphere strength/Earth’s polarity. Nice to know where crust penetration/tremors/tsunamis were significant enough to trigger earthquakes/volcanic activity and consequently further atmospheric dust scatter into the upper atmosphere - the game changer to making this a Global problem.

Just bumped into this which suggests metals are in the mix in a ready form to probably help catalyse aspects of incandescence seen in some impacts. https://www.space.com/metals-detected-in-comet-atmospheres

Thanks for that answer, M.W. ….Happy to let H2O be the main catalyst here.😄 … Although tektite glass beads sampled at the site of many asteroid impacts is apparently also found in the waste of nuclear reactors. 🤔 [I recently read the Nördlinger Ries/Steinheim binary asteroid hit (during the Middle Miocene period - which probably contributed to the Middle Miocene Disruption/extinction?) - produced 24km/4km wide impact craters which threw tektites 450 kms apparently - tiny diamonds were created - impact velocity ~20km/s generating an explosive force equivalent to 1.8 million Hiroshima bombs] …. I saw a picture recently showing the Moon with a thin misty haze (sublimated gases and moisture?) hugging the surface … suggesting a v. weak thin atmosphere still exists even today (mostly at dawn/dusk in the lunar cycle?) … This suggests the lunar core may still be molten and the magnetosphere v. weak - but active? My guess is the Moon’s atmosphere was probably a bit thicker with more water/gas vapour sublimation when Tycho hit - that might have ‘lit the fuse’ before it likely hit a reservoir of ‘Volvic’ condensate trapped just below the lunar surface🤔 - Do you think that could give you the explosive event needed to throw incandescent fragments 5,200 km? With these tektite “glass” dusts being v.resistant to lunar weathering - who can guess when Tycho hit? … possibly much earlier than some predictions. This interesting article was dropped by Barry Fitz-Gerald in my recent thread on Lunar Fluorescent Sources. http://www.psrd.hawaii.edu/Sept04/LunarRays.html Easy to confuse ‘fresh impact’ dusts with elements with a natural high albedo. High reflective index materials found in impact scatter. TiO2 Titanium dioxide occurs in nature as the minerals rutile and anatase. Additionally two high-pressure forms are known minerals: a monoclinic baddeleyite-like form known as akaogiite, and the other is an orthorhombic α-PbO2-like form known as brookite, both of which can be found at the Ries crater in Bavaria.[8][9][10] It is mainly sourced from ilmenite ore. This is the most widespread form of titanium dioxide-bearing ore around the world. Rutile is the next most abundant and contains around 98% titanium dioxide in the ore. The metastable anatase and brookite phases convert irreversibly to the equilibrium rutile phase upon heating above temperatures in the range 600–800 °C (1,110–1,470 °F)Titanium dioxide (B) is found as a mineral in magmatic rocks and hydrothermal veins, as well as weathering rims on perovskite. TiO2 also forms lamellae in other minerals. Titanium dioxide is the most widely used white pigment because of its brightness and very high refractive index, in which it is surpassed only by a few other materials (see list of indices of refraction). Titanium dioxide crystal size is ideally around 220 nm (measured by electron microscope) to optimize the maximum reflection of visible light. However, abnormal grain growth is often observed in titanium dioxide, particularly in its rutile phase. The occurrence of abnormal grain growth brings about a deviation of a small number of crystallites from the mean crystal size and modifies the physical behaviour of TiO2. The optical properties of the finished pigment are highly sensitive to purity. As little as a few parts per million (ppm) of certain metals (Cr, V, Cu, Fe, Nb) can disturb the crystal lattice so much that the effect can be detected in quality control. It is often referred to offhandedly as "brilliant white", "the perfect white", "the whitest white", or other similar terms. Opacity is improved by optimal sizing of the titanium dioxide particles. Silicon Carbide Ferdinand Henri Moissan discovered the very rare naturally occurring SiC mineral while examining rock samples found in the Canyon Diablo meteorite in Arizona. The mineral was named moissanite in his honor. Moissan also synthesized SiC by several routes, including dissolution of carbon in molten silicon, melting a mixture of calcium carbide and silica, and by reducing silica with carbon in an electric furnace

Interesting you mention this …. the critical factors that turn large impact events into a domino effect leading to ‘mass extinction’. …. knock out a few key species in one part of the Planet … and the whole food chain comes crashing down! New vegetation/new species evolution takes over completely.

Is it fair to say that although Aristarchus is older it’s still possible to see it’s scatter patterns are very different to the extreme star light rays of Tycho’s ejecta?. Aristarchus to me(only?)seems like a dull ‘thud meteor’ with it’s ejecta thrown up - then landing in the vicinity …. where as Tycho on the surface seems more high % metalled/composite comet - exploding in the Tunguska mould but not fragmenting the same way at all … a higher speed of object to Aristarchus creating a deeper crater … but projecting distinct fragments shot laterally like a firework over 5,000km .… at extreme speed, each fragment burning out an individual tapering scatter pattern - fine debris of high albedo reflective ‘glass-locked’ composites that have proven to be understandably very resistant to weathering! Is it likely a heavily metalised composite comet would contain the % water needed to catalyse this degree of flash explosion? M.W? If the water % of the Tycho incident was not sufficient …. can I suggest in this period of Lunar history, the Moon might have had a greater atmosphere and intact subterranean condensate chambers of water created by considerable volcanism? … Tycho’s high metal composite comet incoming then could have had it’s head struck alight by a lingering lunar atmosphere and it’s hot body plunged into a condensate water-rich sublimate area of the lunar surface … Bingo! …. extreme sparks! Does that sound plausible? [Comment … I like to think these condensate reservoirs are probably littered around the base of every super volcano in our Solar System where a network of chambers formed as gases were trapped beneath the hard crust … and as activity died, this condensate collected. For me, the presence of rilles is a surefire way to pick out which craters on the moon are impact and which are old, well-weathered, low-lipped lava-filled long dead super volcanoes that created the Mares. Guess it’s courting controversy to suggest Herodotus and Prinz are probably not impacts? What’s your view? Note the number of rilles around these two that are formed from the eye of a meteor impact? - Ivan, Vera and Aristarchus B …. long after H+P died a volcanic death with the crater filled … I feel water ooze created these rilles - not lava]. Getting back to these explosive impacts - It’s arguable the sustained light generated by some Moon impacts and Tunguska seems to be so bright and prolonged, in some instances for several seconds, to suggest some sort of ‘chain reaction’ is happening at the heated pressure head of these fast moving projectiles? This reaction seems to intensify enormously when they hit an ‘atmosphere’ - often resulting in shattering explosions before ‘vaporising’ mostly to dust - there’s a possibility whatever made up the harder core of the Tunguska ‘bomb’ could still be in the marsh? - and the Bologna team are probably on to something significant that makes a lot of sense in the circumstances … especially in relation to the aftershock and tremors recorded by witnesses who were there at the time. Dismissing this first hand account testimony is not something modern day scientists should be doing … especially when physical evidence is proving quite elusive. Maybe translating all the Russian reports/studies … tooth-combing them for additional evidence might give clues … and be the best 1st step before proposing new field studies, possibly in other likely impact locations? - flying in modern equipment utilising more advanced analysis techniques with Russian colleagues.

Thanks for those very interesting links Dave … that Chelyabinsk article was a pleasure to read and comprehensive … The ‘serious’ offering, however, was a challenge of endurance - 65 pages(!) … but at least it gets us closer to the chemistry and mechanisms that explain why some impacts are more explosive and damaging than others. Thank the Gods for the Tunguska marshes and Lake Cheko/Chebarkul being able to absorb some of the more damaging aspects of these impacts. It’s surprising how different explosive events and scatter patterns can be … even on other planets/moons with limited atmospheres and less varied substrates than planet Earth provides. eg: impacts like Tycho V Aristarchus (5200km spread V more localised spread) …. It’s also nice to get clues from these reports about what metals/minerals/composites/coatings it’s best to avoid when designing the skins of re-entry vehicles.😋 - I hear the new Sun probes had a major breakthrough when they were able to develop a skin coating tested to protect measuring instruments from some of the worst ravages of solar radiation … let’s hope it works.

Apologies, I meant atom-rich compared to outside Earth’s atmosphere! … and getting richer as the object gets nearer the Earth’s surface. Robert Frost, Instructor and Flight Controller at NASA said this interesting comment about objects entering Earth’s atmosphere: “Objects that enter Earth’s atmosphere burn not because they are falling from great height, but because they are traveling through the atmosphere at great speed. A returning spacecraft enters the atmosphere at about Mach 25. It’s usually assumed that the mechanism of heating in re-entry is by friction (i.e. viscous drag in the atmosphere). This is the predominant mechanism only at lower altitudes, as air density increases. During the fastest and hottest part of the descent, something different happens. A re-entering vehicle develops a very energetic pressure wave at its leading surfaces. The energy density is sufficient to cause atmospheric molecules to dissociate, and their component atoms to become ionized. The vehicle thus descends in a superheated shroud of incandescent plasma. Plasma does not conform to the gas laws of conventional thermodynamics, although it does share one familiar property—a proportionality between pressure and temperature in a contained system. The formation of the pressure wave, therefore, also creates extreme temperatures. The plasma stream is electrostatically charged, too, and so it concentrates at acute surface contours. The resultant effect is particularly intense local heating at the airframe’s leading edges. An approximate rule-of-thumb used by heat shield designers for estimating peak shock layer temperature is to assume the air temperature in Kelvin to be equal to the entry speed in meters per second—a mathematical coincidence. For example, a spacecraft entering the atmosphere at 7.8km/s would experience a peak shock layer temperature of 7800 K.” Do you think it’s possible that pressure/friction and heat are fractionating a plasma/burn effect wherever water is either trapped in rock - or present in the atmosphere? - to act as a catalyst at the front end of a moving object travelling at a critical velocity? If certain piezoelectric minerals are present (to provide the electrostatic charging mentioned by R. Frost) … and you add metals to this mix … (eg:magnesium) which burn up in our atmosphere easily with bright incandescence … is it possible this accounts for the ‘oxy-acetylene-type effect’ we see in meteor burn up? I’m trying to think of other elements present - beside hydrogen and oxygen - that might catalyse this - Anyone got any other candidates or mechanisms?

That speed differential is a v.interesting observation, Ico … Thinking aloud off the cuff … most photos of comets seem to have a giant rock at the core … so for the Tunguska version to suddenly explode as ‘just a gaseous event’ seems rather unlikely? …. If further Lake study reveals the comet’s main core was gratefully neutered in a swamp ….these may explain the few traces of what caused a huge blast in Earth’s oxygen/hydrogen-rich atmosphere, intense burn up and ground aftershocks. Maybe this swamp saved Humanity from another major extinction event. I feel something unique must be happening to turn a largely invisible inert asteroid rock tumbling through space into a gravity-influenced regular Comet visitor whipped up into an accelerated trajectory that streams a steady trail of fluorescent debris visible to the naked eye each time it passes by. Here’s an interesting one …. Note the ‘lion’s mane’ wicking of the rock … and striations down the rear flank of this beast. It suggests the speed of this projectile has reached a critical heat level as it shows itself to viewers nearing the Sun in it’s periodic fly-bys - possibly generating a transformation to a small degree - ‘burn’ on the surface … probably enough to scatter a steady trail of basaltic glass/dust/rock melt trapped with water vapour to give the fine particulate an extra albedo reflectance to the naked eye as the comet’s tail? Speed may be critical in generating a little EXTRA comet+tail visibility in Space by this known effect when gases are pushed around a rapidly moving object: The ‘wing tip vortices’ effect - as explained here: https://www.sportskeeda.com/f1/wingtip-vortices-in-formula-one-why-are-they-formed …. this happens admittedly in Earth’s unique atmosphere … even small model aircraft generate it at much slower speeds … but could be happening to some objects in Space hitting areas of different gases and sublimated water molecules floating around? … an idea worth consideration.

In this particular case the detail in the Italian report looked to have field research results and analysis presented. … have the Russian team published additional research? I’m not sure what mechanism in nature can make comets/meteors of differing core materials explode so spectacularly and leave so few traces. It happens so rarely, I guess it’s a bit early to write the rule book on whether there will be debris or not? Every case will be unique. Fission/fusion/other - as long as it has the force to flatten trees? I guess the Universe has enough nuclear reactive tricks up it’s sleeve to keep most people happy. Tycho exploded on the Moon surface propelling debris 5,200 km … maybe a similar mechanism to that happened here? I know the Russians were distracted by a Revolution a few years after this impact … and with it happening in such a remote relatively inaccessible region, maybe an Italian team going in and coming up with something ‘new’ probably ruffled a few feathers?! Hard to knock the 100 years of Russian research already done - or Italian research in general …. but this particular Russian paper looked a bit light on science - compared to the Bologna University piece. If locals hadn’t noticed a hole in the ice of Lake Cherbakul soon after the winter impact of the Chelyabinsk meteor … the largest lump of that event would probably have been lost to science and disappeared unnoticed. I reckon you should dispatch a Sidney team to Lake Cheko asap … and clear up this mystery! 😋 Still plenty of science to be done on any samples still lying around. Modern day testing of tree bark fragments might throw up some interesting additional info.

Quite like that explanation, Icosahedron… a comet with a core lump that creates a natural nuclear explosion at it’s high velocity hub end where pressure, temperature and colliding neutrons/particles of certain elements are catalysed to chain-react by the moisture-laden upper atmosphere - H2+O2 split into it explosive basics fuelled by what is in any meteor/comet core? A low trajectory burn up, flattened/scorched trees from an enormous shock wave, embedding fragments in bark - with the heart of the comet being less fragmentary than the Chelyabinsk Incident … dropping in isolated marshy ground … redesigning a lake ( in an area largely unnoticed and unexplored for nearly 100 years) … … sounds like a rough outline with elements that might work? - if nuclear physicists think the right conditions exist here to create sufficient damage?

…. it just those two long pesky rays of narrow scatter to the west that makes the split idea attractive and distracting … wonder if they’ve managed to replicate that in lab impact experiments with fragments of a certain shape/size? … guess there is more to Life, Living and Meaning to be over-analysing stuff like this! 😋 …. how important is it in the Big Picture? …. Is it best to put this one in the Pending tray of Improbability? - Best I move on to shortly replying to those other points you made earlier - [discussing ideas around the chemical signatures that may be creating weathering-resistant high albedo traces like Tycho/Copernicus, the evidence Herodotus and Prinz may be long dead craters of super volcanoes, plus certain conditions that might be forming some rilles in our solar system] …