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| John Curtis... |
 Posted: Thu Sep 24, 2009 7:46 am |
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Lunar water in the news:
http://www.space.com/scienceastronomy/090923-moon-water-discovery.html
Moon rocks originated as precipitates at a seafloor volcano.
http://www.pmel.noaa.gov/vents/chemistry/images/vents2.gif
In the plume of the volcano, second item after 3He, is silicic
acid, H4SiO4, the source of ~90% of moon rocks.
Silicic acid results from reversible hydration of volcanic
silicon: Si + 4H2O <-----> H4SiO4 + 4H+
On contact with iron or magnesium, silicic acid gives up
four protons and precipitates as olivine, main constituent of
mare basalts: H4SiO4 + Mg + Fe <---> FeMgSiO4+ 4H+
Similarly, aluminum and calcium combine with silicic
acid to form anorthite, the main component of lunar
highlands: 2H4SiO4 +2Al + Ca <---> Ca(AlSiO4)2 + 8H+
Resupplying protons (H+) in the form of acid or solar wind
should liberate water from the moon rocks. John Curtis |
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| dlzc... |
| Posted: Thu Sep 24, 2009 12:42 pm |
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Dear Yousuf Khan:
On Sep 24, 1:19 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
....
[quote:1c99cd4515]Okay, so we know that water can get recycled
in the rocks of the Moon. But what implications
are there for the origin of the Moon?
[/quote:1c99cd4515]
Nothing definitive. Both Venus and Mars have some water, so this just
means that (as I see it) the Moon has been where it is for a very long
time.
[quote:1c99cd4515]Now that water has been found, is the Giant
Impactor Theory still needed?
[/quote:1c99cd4515]
Yes, or something very like it.
[quote:1c99cd4515]Or worse yet, does the Giant Impactor actually
contradict water being found on the Moon?
[/quote:1c99cd4515]
No, I don't see that it speaks to this at all. We know the Moon has
been around for at least 2.2 billion years. Plenty of time to bombard
surface layers with protons from solar wind, that can in turn liberate
oxygen and start the process of water / hydrate formation. Or was
simply carried from the merging of Theia and proto-Earth.
How far down does the "water" go?
David A. Smith |
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| Yousuf Khan... |
| Posted: Thu Sep 24, 2009 2:19 pm |
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John Curtis wrote:
[quote:fce5d5a9ea]In the plume of the volcano, second item after 3He, is silicic
acid, H4SiO4, the source of ~90% of moon rocks.
Silicic acid results from reversible hydration of volcanic
silicon: Si + 4H2O <-----> H4SiO4 + 4H+
On contact with iron or magnesium, silicic acid gives up
four protons and precipitates as olivine, main constituent of
mare basalts: H4SiO4 + Mg + Fe <---> FeMgSiO4+ 4H+
Similarly, aluminum and calcium combine with silicic
acid to form anorthite, the main component of lunar
highlands: 2H4SiO4 +2Al + Ca <---> Ca(AlSiO4)2 + 8H+
Resupplying protons (H+) in the form of acid or solar wind
should liberate water from the moon rocks. John Curtis
[/quote:fce5d5a9ea]
Okay, so we know that water can get recycled in the rocks of the Moon.
But what implications are there for the origin of the Moon? Now that
water has been found, is the Giant Impactor Theory still needed? Or
worse yet, does the Giant Impactor actually contradict water being found
on the Moon?
Yousuf Khan |
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| John Curtis... |
| Posted: Fri Sep 25, 2009 5:17 am |
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On Sep 24, 1:19 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
[quote:7fbd3f0fc0]John Curtis wrote:
Moon rocks originated as precipitates at a seafloor volcano.
http://www.pmel.noaa.gov/vents/chemistry/images/vents2.gif
In the plume of the volcano, second item after 3He, is silicic
acid, H4SiO4, the source of ~90% of moon rocks.
Silicic acid results from reversible hydration of volcanic
silicon: Si + 4H2O <-----> H4SiO4 + 4H+
On contact with iron or magnesium, silicic acid gives up
four protons and precipitates as olivine, main constituent of
mare basalts: H4SiO4 + Mg + Fe <---> FeMgSiO4+ 4H+
Similarly, aluminum and calcium combine with silicic
acid to form anorthite, the main component of lunar
highlands: 2H4SiO4 +2Al + Ca <---> Ca(AlSiO4)2 + 8H+
Resupplying protons (H+) in the form of acid or solar wind
should liberate water from the moon rocks. John Curtis
Okay, so we know that water can get recycled in the rocks of the Moon.
But what implications are there for the origin of the Moon? Now that
water has been found, is the Giant Impactor Theory still needed? Or
worse yet, does the Giant Impactor actually contradict water being found
on the Moon?
Hydration of silicon, thus the formation of silicates, requires[/quote:7fbd3f0fc0]
pressures of ~250 atmospheres. On Earth such pressures are
found at ocean depth of ~2.5 km. Because of lesser gravity,
Moon's ocean had to be ~15 km deep in order to generate
pressures necessary for the formationof moon rocks.
A deep ocean on the Moon does not favor impact origin.
John Curtis |
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| dlzc... |
| Posted: Fri Sep 25, 2009 10:08 am |
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Dear John Curtis:
On Sep 25, 8:17 am, John Curtis <j... at (no spam) curtis.ms> wrote:
....
[quote:2e7ac16b8e]Hydration of silicon, thus the formation of silicates,
requires pressures of ~250 atmospheres.
[/quote:2e7ac16b8e]
At STP. When said hydrogen has to be dissociated from water. When
hydrogen is not arriving at many kilometers per second.
[quote:2e7ac16b8e]On Earth such pressures are found at ocean depth
of ~2.5 km. Because of lesser gravity, Moon's
ocean had to be ~15 km deep in order to generate
pressures necessary for the formation of moon
rocks.
[/quote:2e7ac16b8e]
Or the rocks came from the Theia+proto-Earth assembly.
[quote:2e7ac16b8e]A deep ocean on the Moon does not favor
impact origin.
[/quote:2e7ac16b8e]
Yes, it requires more / different.
David A. Smith |
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| YKhan... |
| Posted: Fri Sep 25, 2009 11:25 am |
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On Sep 24, 6:42 pm, dlzc <dl... at (no spam) cox.net> wrote:
[quote:598b3fa366]On Sep 24, 1:19 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
Okay, so we know that water can get recycled
in the rocks of the Moon. But what implications
are there for the origin of the Moon?
Nothing definitive. Both Venus and Mars have some water, so this just
means that (as I see it) the Moon has been where it is for a very long
time.
[/quote:598b3fa366]
Well, the Moon would have been there for a very long time, no matter
what theory you subscribed to.
[quote:598b3fa366]Now that water has been found, is the Giant
Impactor Theory still needed?
Yes, or something very like it.
[/quote:598b3fa366]
Well, wasn't the Theia theory proposed mainly because the Apollo
samples came back with little trace of water?
Now that water has been found, old theories that were once dismissed
due to the lack of water are now valid again. Such hypotheses as Co-
formation, Fission, and maybe even Capture might be back on the table
again. The first two might be stronger candidates than the third
though.
http://en.wikipedia.org/wiki/Moon#Origin_and_geologic_evolution
[quote:598b3fa366]Or worse yet, does the Giant Impactor actually
contradict water being found on the Moon?
No, I don't see that it speaks to this at all. We know the Moon has
been around for at least 2.2 billion years. Plenty of time to bombard
surface layers with protons from solar wind, that can in turn liberate
oxygen and start the process of water / hydrate formation. Or was
simply carried from the merging of Theia and proto-Earth.
[/quote:598b3fa366]
Now, I thought most of the water on Earth came from the Late Heavy
Bombardment, when the Moon was already supposed to have been fully
formed. Or was there already water on the Earth beforehand?
[quote:598b3fa366]How far down does the "water" go?
[/quote:598b3fa366]
So far, they only know about it going down to the top layers of the
surface, *all* over the Moon. But if it's on the surface, then it's
likely to be below as well. Is it is possible that there are
underground rivers? Hard to say. If there were underground rivers,
then they would have to be very deep underground, otherwise some of
them would've shown signs at the surface, wouldn't they?
Yousuf Khan |
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| YKhan... |
| Posted: Fri Sep 25, 2009 11:26 am |
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On Sep 25, 11:17 am, John Curtis <j... at (no spam) curtis.ms> wrote:
[quote:2ee5f9f4f6]Hydration of silicon, thus the formation of silicates, requires
pressures of ~250 atmospheres. On Earth such pressures are
found at ocean depth of ~2.5 km. Because of lesser gravity,
Moon's ocean had to be ~15 km deep in order to generate
pressures necessary for the formationof moon rocks.
A deep ocean on the Moon does not favor impact origin.
John Curtis
[/quote:2ee5f9f4f6]
I thought that these hydration events happened as a result of the
solar winds, rather than great pressures?
Yousuf Khan |
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| dlzc... |
| Posted: Fri Sep 25, 2009 1:03 pm |
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Dear YKhan:
On Sep 25, 2:25 pm, YKhan <yjk... at (no spam) gmail.com> wrote:
[quote:84a88f60cb]On Sep 24, 6:42 pm,dlzc<dl... at (no spam) cox.net> wrote:
On Sep 24, 1:19 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
Okay, so we know that water can get recycled
in the rocks of the Moon. But what implications
are there for the origin of the Moon?
Nothing definitive. Both Venus and Mars have
some water, so this just means that (as I see it)
the Moon has been where it is for a very long
time.
Well, the Moon would have been there for a very
long time, no matter what theory you subscribed to.
[/quote:84a88f60cb]
Unless you believe in biblical creation some thousands of years ago,
of course...
[quote:84a88f60cb]Now that water has been found, is the Giant
Impactor Theory still needed?
Yes, or something very like it.
Well, wasn't the Theia theory proposed mainly
because the Apollo samples came back with
little trace of water?
[/quote:84a88f60cb]
I thought it was proposed because we cannot figure how Earth can
closely capture a body of the Moon's size.
[quote:84a88f60cb]Now that water has been found, old theories
that were once dismissed due to the lack of
water are now valid again.
[/quote:84a88f60cb]
Maybe.
[quote:84a88f60cb]Such hypotheses as Co-formation, Fission, and
maybe even Capture might be back on the table
again. The first two might be stronger candidates
than the third though.
[/quote:84a88f60cb]
Well, Theia and Fission are very closely related. I just don't think
this "surface water" can help sort them out any better.
[quote:84a88f60cb]http://en.wikipedia.org/wiki/Moon#Origin_and_geologic_evolution
Or worse yet, does the Giant Impactor actually
contradict water being found on the Moon?
No, I don't see that it speaks to this at all. We
know the Moon has been around for at least 2.2
billion years. Plenty of time to bombard surface
layers with protons from solar wind, that can in
turn liberate oxygen and start the process of
water / hydrate formation. Or was simply carried
from the merging of Theia and proto-Earth.
Now, I thought most of the water on Earth came
from the Late Heavy Bombardment,
[/quote:84a88f60cb]
Or the Great Oxidation Event, which is also late.
[quote:84a88f60cb]when the Moon was already supposed to have
been fully formed. Or was there already water on
the Earth beforehand?
[/quote:84a88f60cb]
LIttle evidence of much water before 2.2 Gy, that I know of. Bit out
of my area of familiarity...
[quote:84a88f60cb]How far down does the "water" go?
So far, they only know about it going down to the
top layers of the surface, *all* over the Moon.
But if it's on the surface, then it's likely to be
below as well.
[/quote:84a88f60cb]
Do you remember reports of "dirty snowballs" being reported as falling
into Earth's atmosphere some time ago? There is no requirement for
the water to be any deeper than the surface, sublime directly to water
vapor, and leave for space again.
[quote:84a88f60cb]Is it is possible that there are underground
rivers? Hard to say.
[/quote:84a88f60cb]
We did do sounding with Apollo, and we got no significant echos for
hundreds of miles down. Not that we had the technology in those ships
to discern really fine structures most likely.
[quote:84a88f60cb]If there were underground rivers, then they would
have to be very deep underground, otherwise some of
them would've shown signs at the surface, wouldn't they?
[/quote:84a88f60cb]
Yes, absolutely. These "wet spots" seem like they were "come and go"
though, so I'll argue "dirty snowballs" until we can get back...
David A. Smith |
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| Androcles... |
| Posted: Sun Sep 27, 2009 1:42 am |
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"Yousuf Khan" <bbbl67 at (no spam) spammenot.yahoo.com> wrote in message
news:4abf16b7 at (no spam) news.bnb-lp.com...
[quote:910554337a]N:dlzc D:aol T:com (dlzc) wrote:
"Yousuf Khan" <bbbl67 at (no spam) spammenot.yahoo.com> wrote in message
Well, then it was proposed in opposition to the Capture
theory. That would put it in the same category of theories
along with Fission, and Coformation. So there must've
been a compelling reason to choose that over Fission
and Coformation? Did Theia result in less water being transferred to the
Moon than the other non-Capture
theories?
If there was free water at the time that the Moon "lobed off", and the
shape of the lobe pulled lighter materials to the Moon, then water was
certainly lighter. It could have splashed back, of course, but I would
expect there to have been no significant surface water when any sort of
lobing / collision would have vaporized it.
When a planetesimal is being formed, why should its water only be sitting
on the surface? Water is not a light molecule,
[/quote:910554337a]
Idiot. |
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| Odysseus... |
| Posted: Sun Sep 27, 2009 2:13 pm |
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In article <4abf16b7 at (no spam) news.bnb-lp.com>,
Yousuf Khan <bbbl67 at (no spam) spammenot.yahoo.com> wrote:
<snip>
[quote:ab9182f0d0]I must say I'm a bit surprised that there's still so much cometary
matter left in the inner solar system after so many billions of years
after the formation of the Solar system.
I wonder if they have any relationship to the noctilucent clouds that
you mentioned once?
Noctilucent cloud - Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Noctilucent_cloud
[/quote:ab9182f0d0]
Rather the "zodiacal light", I expect.
<http://en.wikipedia.org/wiki/Zodiacal_light>
--
Odysseus |
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| YKhan... |
| Posted: Mon Sep 28, 2009 9:24 am |
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On Sep 27, 12:52 pm, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net>
wrote:
[quote:f96705d64d]"Yousuf Khan" <bbb... at (no spam) spammenot.yahoo.com> wrote in message
N:dlzc D:aol T:com (dlzc) wrote:
"Yousuf Khan" <bbb... at (no spam) spammenot.yahoo.com> wrote in message
Well, then it was proposed in opposition to the Capture
theory. That would put it in the same category of theories
along with Fission, and Coformation. So there must've
been a compelling reason to choose that over Fission
and Coformation? Did Theia result in less water being
transferred to the Moon than the other non-Capture
theories?
If there was free water at the time that the Moon "lobed
off", and the shape of the lobe pulled lighter materials to
the Moon, then water was certainly lighter. It could have
splashed back, of course, but I would expect there to
have been no significant surface water when any sort of
lobing / collision would have vaporized it.
When a planetesimal is being formed, why should its
water only be sitting on the surface? Water is not a light
molecule, like hydrogen by itself, it's actually quite heavy
and dense.
Not compared to rock. Not compared to all the bodies documented
in the solar system. They all average to be more dense than
water.
[/quote:f96705d64d]
Well, I would expect that the water that came with the rocks was
probably trapped inside air pockets inside the rock. Then as more
rocks came crashing down, more air pockets with water in it. As the
rocks were liquefied the air pockets of water vapor probably joined
together over millenia to form bigger pockets. Then the steam came
bursting out with volcanism. But before the volcanism, the water was
probably well distributed all over the Earth.
[quote:f96705d64d]As more and more rocks are crashing down, whatever
water was already there inside whatever rocks should
get buried by the new rocks.
No. Plus the "crashing down" has a lot of energy to disspate.
Enough to melt rock, more than enough to vaporize water.
[/quote:f96705d64d]
Yes, which will liquefy the rocks and make it easier for pockets of
air and steam to consolidate into larger pockets.
[quote:f96705d64d]So there should be an even distribution of water
throughout the volume of the planetesimal as it is forming into
a planet. Water probably first comes to
the surface in early volcanic eruptions, and settles
down on the surface as rocks get cooler and more
impermeable, keeping water from seeping back down.
No, this does not work.
[/quote:f96705d64d]
Why not?
[quote:f96705d64d]So if a piece of an early-stage planet is being "lobed"
off, that rock is bound to contain as much water as
any other piece of rock on that planet.
Agreed. Which is in the form of hydrates, with very little free
water.
[/quote:f96705d64d]
I'm sure water can be mixed in with other chemicals to be transported
around, but I'm sure water can be transported around on its own merits
too.
[quote:f96705d64d]It won't be on the surface of the planet, it will be
inside the molten rock.
No, only in free fall. Water can dissolve into molten rock, but
will dissociate quite readily and change the rock's chemistry.
[/quote:f96705d64d]
Even if they dissociate into the rock, the fact that they're buried so
deeply down inside the planetesimal, they have time to reassociate
before it comes steaming out. Unlike in space, dissociated water isn't
lost forever, inside the planetesimal they keep mixing it up with each
other.
[quote:f96705d64d]I've posted links about this before, but current thinking
is that a nickel famine killed off most of the methanogenic
bacteria, 2.4 billion years ago.
Nickel Down, Oxygen Up / Science News
"Billions of years ago, methane-producing bacteria
called methanogens thrived in nickel-rich seas. The
high amounts of methane that this early life pumped
into the environment prevented oxygen accumulation
in the atmosphere because the methane reacted with
any oxygen, creating carbon dioxide and water, the
researchers suggest."
http://www.sciencenews.org/view/generic/id/42580/title/Nickel_down,_o...
Methanogenic bacteria produced methane which
would react with oxygen to produce only carbon
dioxide and water.
Only if there was a spark, and only above a certain balance
(range) between oxygen and methane.
[/quote:f96705d64d]
I'm sure there was enough lightening around to cause that spark back
then. Maybe there was even more lightening on that early Earth?
[quote:f96705d64d]So these things were producing more and more water
on Earth in the early days. So there should've been no lack of
water back then, just a lack of oxygen.
I'll accept this.
[/quote:f96705d64d]
Okay.
[quote:f96705d64d]House-sized comets are falling on Earth continuously?
Wow! So you're saying if they're falling on the Earth,
then they must be doing the same on the Moon?
How could they not?
[/quote:f96705d64d]
On the Moon with a lack of an atmosphere, we should be seeing new
craters being formed, laden with water.
[quote:f96705d64d]Noctilucent clouds had never been seen prior to the 1800s. So
either we've had an increase in cometary material coincident with
the Industrial Revolution, or no.
[/quote:f96705d64d]
Or nobody noticed them prior to the 1800's, or just assumed they were
just the same as any other clouds.
[quote:f96705d64d]I suppose the least we can do these days is drop
off a series of automated and self-sustained
seismological stations on the Moon, and wait for
them to measure Moonquakes. I guess moonquakes
would be a major discovery in and of itself.
http://www2.computer.org/portal/web/csdl/doi/10.1109/CIT.2007.91
"... Apollo astronauts brought seismometers to the moon and more
than ten thousand of seismic events are recorded."
How many of those are impactors? How many of those are dirty
snowballs? With a 700 mile thick crust on the Earth-facing
side...
[/quote:f96705d64d]
Okay, I see what you mean, these could be those mini-comets crashing
to the Moon.
[quote:f96705d64d]3-D model shows big body of water in Earth's mantle
http://www.physorg.com/news90171847.html
Something like that within the Moon might work too.
Unlikely over bilions of years, starting with a fully molten
state.
It would seem to me that it would be pretty unlikely for
water to exist in the heat of the Earth's mantle, but there
it is (possibly).
I'd like to see a link. I'd fully expect hydrogen to be released
by our interior "nuclear reactor" (as decayed neutrons), but a
sea-sized body...
[/quote:f96705d64d]
Well, the Earth's nuclear fission reactor is much further down inside
the core, whereas this water is somewhere much higher up in the
mantle. Other than heat transfer, I don't think the nuclear reactor is
producing this water or has any link to this water. The water was
probably already there since the formation of the Earth.
Yousuf Khan |
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| John Curtis... |
| Posted: Wed Oct 28, 2009 3:12 am |
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On Sep 25, 1:08 pm, David A. Smith wrote:
[quote]
Or the rocks came from the Theia+proto-Earth assembly.
Moon rocks were formed insitu. Highlands anorthite[/quote]
is older (4.5 GA) than mare basalt (3.2 GA). The separation
of rocks can be attributed to the odd charge of aluminum (+3)
which on contact with silicate (-4) forms a negatively charged
aluminum silicate (-1), which remains in suspension while being
propelled toward the seashore by the waves. Eventually
aluminum silicate combined with calcium to form highlands
anorthite. John Curtis |
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