[X] My Assistant

[Bob Shaw]

There are crackpot therories of exploding asteroid/comet parent planets or ice-moons, with electrolytic chemical products in their interior making them timebombs waiting to go off... The theories overall are crackpot, but bits and pieces of them may well be valid.  If we ever do get a cryogenic core sample return from a comet's interior, there's lab safety reasons to be sure it stays cold, besides science-value reasons!

Edstrick:

Hey, that's *my* kind of crackpot! Any, er, URLs or whatever (hold your nose when you type!)?

Bob Shaw

[Guest_Richard Trigaux_*]

Some of the ices may even be explosive.  Take simulated Triton surface ices.. Water/Nitrogen/Methane frosts... Irradiate the mix with charged particles, it turns yellow with new compounds..... and it explodes when heated.  There are crackpot therories of exploding asteroid/comet parent planets or ice-moons, with electrolytic chemical products in their interior making them timebombs waiting to go off... The theories overall are crackpot, but bits and pieces of them may well be valid.  If we ever do get a cryogenic core sample return from a comet's interior, there's lab safety reasons to be sure it stays cold, besides science-value reasons!

Not explosive in the common sense of this word. But they could, when heated, say, boil. There is an example of this right on Earth, in the bottoms of the oceans, where "methane ice" can form, a common water ice with methane molecules into the hollows between water molecules. And this stuff can form ices in the bottom of the ocean (and fill pipe lines too). When brough to the surface, this ice-looking stuff melts like ordinary ice, but it boils in the same time while releasing the methane. So similarly such products such as ammonia-water eutectics (In Titan?) could boil when the pressure is released. If there are ice volcanoes (Enceladus, Titan, Triton...?) there could be explosions similar to our lava volcanoes where dissolved gasses drive the lava and project it very violently. But basically all this is just violent outgassing, eventually supersonic, but not detonations with a shock wave and the like.

[edstrick]

"Not explosive in the common sense of this word. But they could, when heated, say, boil."

No.. ... I mean kablooie explode.. there's all sorts of nitrogen double and triple bonds in the radiation induced reaction products and the stuff disassembles itself violently, and I think some lab equipment, as it's warmed up.

Like "Nitrogen-Tri-Iodide", which you can make by soaking iodine grains in household ammonia.. dry the stuff out and it's a contact explosive. Anything bigger than a grain of rice can hurt... big volumes aren't safe even when wet.

<fond memories>

[djellison]

Like "Nitrogen-Tri-Iodide", which you can make by soaking iodine grains in household ammonia.. dry the stuff out and it's a contact explosive.  Anything bigger than a grain of rice can hurt... big volumes aren't safe even when wet.

<fond memories>

VERY fond memories.



Doug

[Bob Shaw]

Not explosive in the common sense of this word. But they could, when heated, say, boil. There is an example of this right on Earth, in the bottoms of the oceans, where "methane ice" can form, a common water ice with methane molecules into the hollows between water molecules. And this stuff can form ices in the bottom of the ocean (and fill pipe lines too). When brough to the surface, this ice-looking stuff melts like ordinary ice, but it boils in the same time while releasing the methane. So similarly such products such as ammonia-water eutectics (In Titan?) could boil when the pressure is released. If there are ice volcanoes (Enceladus, Titan, Triton...?) there could be explosions similar to our lava volcanoes where dissolved gasses drive the lava and project it very violently. But basically all this is just violent outgassing, eventually supersonic, but not detonations with a shock wave and the like.

Methane-Water clathrates are actually fairly widespread on Earth, and are implicated in all sorts of less-than-desirable possibilities, among which are:

- Clathrate layers beneath melting permafrost may release large quantities of methane into the atmosphere, making global warming accelerate

- Oceanic clathrate decomposition may sink ships with no trace (release gas in sufficient quantities on the ocean floor and boats just drop once the density of the medium falls below that of water)

Ah, Thomas Gold, where are you when we need you!

[gpurcell]

Not explosive in the common sense of this word. But they could, when heated, say, boil. There is an example of this right on Earth, in the bottoms of the oceans, where "methane ice" can form, a common water ice with methane molecules into the hollows between water molecules. And this stuff can form ices in the bottom of the ocean (and fill pipe lines too). When brough to the surface, this ice-looking stuff melts like ordinary ice, but it boils in the same time while releasing the methane. So similarly such products such as ammonia-water eutectics (In Titan?) could boil when the pressure is released. If there are ice volcanoes (Enceladus, Titan, Triton...?) there could be explosions similar to our lava volcanoes where dissolved gasses drive the lava and project it very violently. But basically all this is just violent outgassing, eventually supersonic, but not detonations with a shock wave and the like.

My physics teacher made up a batch of this on a sheet of paper. As he was shifting the sheet, it blew...BIG sound, BIG purple cloud of smoke!

[tty]

Methane-Water clathrates are actually fairly widespread on Earth, and are implicated in all sorts of less-than-desirable possibilities, among which are:

- Clathrate layers beneath melting permafrost may release large quantities of methane into the atmosphere, making global warming accelerate

- Oceanic clathrate decomposition may sink ships with no trace (release gas in sufficient quantities on the ocean floor and boats just drop once the density of the medium falls below that of water)

Ah, Thomas Gold, where are you when we need you!

Methane hydrates are indeed widespread on (and in) the ocean floor. It is very likely that the sharp "spike" of very warm climate at the Paleocene/Eocene border was caused by a large methane hydrate "burp".

Here is an image if anyone is interested what the stuff looks like:

www.usssp-iodp.org/ Images/flaming_hydrate.jpg

Methane hydrates are perhaps the most obvious example of a compound that exists on a large scale here on Earth but is unstable at "normal" temperatures and pressures. I am sure the same applies even more to extremely cold/reducing/high-pressure environments elsewhere so I agree that material from e. g. an asteroid or comet must be kept under very carefully controlled conditions both for scientific and safety reason.

An interesting thought: without that "methane burp" 55 million years ago we wouldn't be here. The oldest primates are exclusively North American, but that Paleocene/Eocene spike was warm enough so that primates got across to Europe by way of Canada-Greenland-Svalbard-Scandinavia. In North America primates became extinct long ago but some of those in Europe later migrated to Africa. The rest is history as they say...

tty

[Guest_BruceMoomaw_*]

Unfortunately, Gold's methane-burp theory for ship disappearances just proves again that he had a penchant for unscientific sensationalism -- like his straight-faced theory that the little blobs of glass photographed on the Moon's surface by Neil Armstrong might have been due to a gigantic solar outburst only a few tens of thousands of years ago, and that this might explain the myth of Phaethon. (Or his straight-faced statement shortly before dying that solar sails couldn't possibly work because photon pressure doesn't really exist, although spacecraft have been using it for attitude control since 1964 and it's the only thing that saved Mariner 10.)

We already have a perfectly good natural explanation for some ship disappearances, and IT'S been proven -- SAR satellites have recently proven that 30-meter freak waves (sighted occasionally by surface ships that survived the encounter) really do exist, and in fact are surprisingly common. By contrast, no one seems to have seen a methane burp of any size whatsoever.

[Bob Shaw]

We already have a perfectly good natural explanation for some ship disappearances, and IT'S been proven -- SAR satellites have recently proven that 30-meter freak waves (sighted occasionally by surface ships that survived the encounter) really do exist, and in fact are surprisingly common.  By contrast, no one seems to have seen a methane burp of any size whatsoever.

Bruce:

If you SEE an oceanic burp you're possibly not going to make it back to shore to tell anybody! It's a bit like those 'friendly' dolphins and porpoises who (allegedly) escort lost swimmers back to shore - you'd never hear from anyone who was carefully escorted out to sea instead!

There have been several North Sea trawler sinkings which have happened in good weather, in well travelled seas. The wrecks have been found in good condition, hatches closed etc, on the sea-bed. And considering the amount of natural gas around the near-surface geology in those parts it's probably not even necessary to put forward any of Gold's more outre notions as to the origins of the gas...

The point is, I suppose, that even our own 'stable' environment is subject to a whole range of unexpected but catastrophic changes - just like all the bodies we've looked at which still have any life in them! Well, perhaps not 'life'...

Bob Shaw

[edstrick]

"....By contrast, no one seems to have seen a methane burp of any size whatsoever"

I don't know whether methane blows are enough to sink ships, but several years ago, the Japanese lost a research ship and crew that was investigating the surface roil over a seamount-volcano that was burbling.. My understanding was that it chugged and the ship sank almost without warning in the roil.

[Guest_RGClark_*]

On EARTH, everywhere we find liquid water we find life.  Comet Tempel 1 is nothing like earth and one should be very careful comparing grapes to pumpkins.

Neither is Mars or Europa. But liquid water is the key search point for life on those worlds as well.


Bob Clark

[Guest_RGClark_*]

It should be kept in mind that many of the carbonaceous asteroids had large amounts of WARM liquid water in their interiors, mixed with large amounts of complex organic biological precursors, for tens of millions of years -- much longer than the total liquid-water exposure time of the interior of any comet -- but show no sign of evolving life.  As Chris Chyba says, that's one indication that the evolution of life may not be as easy and inevitable as is widely assumed nowadays, and it certainly speaks strongly against cometary life.

Bruce you should keep in mind that relic life has been claimed to have been present in some carbonaceous meteorites such as the Murchison meteorite.
Also note that some scientists believe comets are the source of carbonaceous meteorites. Strong evidence for this is the large amount of water and organics seen in such meteorites. Another fact arguing strongly in favor of this is that the meteoroids from meteor showers such as the Perseids contain organics and hydrated minerals and we even know the comets these showers stem from.


Bob Clark

[Guest_Richard Trigaux_*]

The stories of ships sunk by methane eruptions is not rumor: there was recently an article in a french science review explaining how it happens, in Northers Sea. You know there are huge gaz deposits there, and some of it slowly leaks through sediments on the ocean floor. AS there are clay layers and sand layers, the leaking is not homogenous, it can form pockets of gas, which can break and left a crater. They were exploring one of these craters, and they were intrigued by a "central peak". They found it was a fisher ship sunken straight on the bottom, still intact. We can imagine a kind of limnic eruption, like the too famous Nyos lake in Cameroun; suddenly the ocean turns red and boils. And, as explained Bob Shaw, the density of the sea lowers (with bubbles of gas) and a ship can sink in some seconds. This is worth the Bermuda triangle story, but with a natural (and frightening) explanation...

There are other parts of the word with undersea mud volcanoes (some are as big a their lava counterparts) emitting enough methane emit flames and even detonate when it reaches the air. Jules Verne described the ones in the Crimea.


The idea of a sun flare large enough to be visible in antic times is not impossible too, although not proven. Many stars emit large flares at intervals, some large enough to roast a Earth-like planet. We do not know why some stars emit large flares and other not, so we cannot be sure that some dis not occured in ancient times, of which ancient myth may remember in their usual symbolic way.


Back to comets, I think all the comets may not have the same history or origin. Some may be loose snow balls; but others may come from the breaking appart of larger bodies, and may thus contain hardened ice, or eventually compounds which formed under pressure, like chlatrates.

[Guest_RGClark_*]

Now, how can you say that?  The item on the mystery of large numbers of "mutilated, bloodless kangaroos" being found in Australia was fascinating.  If there's a pack of vampire kangaroos hopping around in the Outback, wouldn't YOU like to know about it before camping there?

Meanwhile, Hawaii's Jeffrey Bell tells me he's very skeptical of the carbonate detection, because carbonates aren't being found in the cometary dust particles collected by U-2s from Earth's stratosphere.  Question: could vaporized carbonates have been formed on the spot in the very high-temperature gases produced by the Impactor's impact, out of the carbonaceous-chondrite dust and CO2 in the comet?  Indeed, could both carbonates and the detected CO2 have been formed out of a quick reaction between the chondrite dust and the oxygen released by the high-temperature breakdown of water ice?  (He also tells me that "Linda Moulton Howe... is a regular on the Art Bell show and has a long history of zany pseudoscientific beliefs.  Back in the 1980s she pretty much created the modern myth of cattle mutilations by UFOs and/or black helicopters."  However, I don't see any obvious BS in her quotes from Lisse, and Paul Anderson tells us he heard Lisse saying the same things in person.)

Bruce, carbonate HAS been observed in interplanetary dust particles (IDPs):

Carbonate Mineralogy in Stratospheric IDPs: Compositions, Co-Existing Smectite and Comparison to CI Carbonaceous Chondrites.
D. J. Joswiak and D. E. Brownlee, Dept. of Astronomy, Box 351580, University of
Washington, Seattle, WA 98195, e-mail: joswi**@*****.washington.edu, brownl**@*****.washington.edu
http://www.lpi.usra.edu/meetings/lpsc2001/pdf/1998.pdf

Perhaps you could do an interview with Lisse to establish the validity of these detections.


Bob Clark

[Guest_RGClark_*]

Carbonates does not necessary need liquid water to form. They can also form in volcanoes, and there are several instances of carbnate lavas, in Africa and even in Europe. Carbonate lavas may form from phase separations in magmatic chambers, being not mixible with silicate lavas. I must confess I do not really understant how carbonates may sustain such high temperatures: when you heat limestone, it does not melt, instead it decomposes and form lime and carbon dioxid. Maybe carbonatite lavas are mixtures which melt at about 400-500° without decomposing.

And when we look at Temple II it really looks like a complex body exhibiting layers and varied structures. So it may be a part of a much larger body where many chemical reactions were possible. It may happen that even the coldest bodies in the Kuyper belt or Oort belt may have experienced ennough heat during their accretion to have liquid water inside. BruceMoomaw also have arguments to have some caution about carbonates.

That does not mean life, as life requires a constant source of energy to evolve, even the simplest living being consume high energy food and release low energy wastes. They need a medium with somewhere an energy source. Living beings are thermal machines (more complex, but the overal working of a food chain is that of a thermal machine) so they cannot exist in a medium in thermal equilibrium such as the hot inside of a newly accreted body. At best they could oxyde reactive chemical items, but this could last only a while, when the appearance of life may require millions of years.
....

Rich, thanks for the info on carbonate lavas. I had not seen that before. As a first guess perhaps it could be the high pressure deep underground allows water to remain liquid to allow carbonate to form. It is notable for instance these lavas, though far above 100 C, are still far cooler than most other lavas.
Actually this info on carbonate lavas may be useful for another idea I'm investigating. Let's just say it involves a very warm place in the Solar System.




Bob Clark