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Fraser
2005-May-13, 04:48 PM
SUMMARY: Scientists have had an opportunity study much of the data sent back by Cassini about the composition of Titan's atmosphere - it's more familiar than you would think. The thick atmosphere is rich in organic compounds, which are similar to conditions that might have been found early in the Earth's history. The Cassini science team also found a vortex above Titan's north pole, which is very similar to the situation on Earth that leads to the ozone hole. Titan has no ozone, but this polar vortex isolates gas during winter and could allow complex chemistry to occur.

View full article (http://www.universetoday.com/am/publish/titan_atmosphere_familiar.html)

What do you think about this story? Post your comments below.

om@umr.edu
2005-May-14, 12:13 PM
I doubt if Earth's early atmosphere was rich in organic compounds.

The two elements that make hydrocarbons, C and H, are mostly found in the outer parts of the solar system. Those elements are accompanied by "strange" Xe in meteorite inclusions as well as in Jupiter (with twice the "normal" abundance of Xe-136).

On the other hand Earth and the other rocky planets close to the Sun are made mostly of Fe, O, and S. Those elements are accompanied by "normal" Xe, in meteorite inclusions as well as in Earth and Mars.

Nobody has reported the presence of "strange" Xe on Earth.

It is most unlikely that early Earth had the mix of light elements seen today in the outer part of the solar system.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-14, 02:00 PM
Originally posted by om@umr.edu@May 14 2005, 12:13 PM
I doubt if Earth's early atmosphere was rich in organic compounds.

I doubt that the very early earth's atmosphere was AS RICH AS TITAN's is now, but I think the evidence supports the idea that there were more organic compounds, and lots of methane and ammonia than we have now. The biggest difference between Earth and Titan is at on the Earth we have had active processes to convert these compounds to other forms, and the heat to boil the lighter ones away. One need only look at the small amount of Carbon on our planet to recognize that we couldn't have been as rich with it as Titan is Even if all our Carbon used to be in the atmosphere, there's not enough.


It is most unlikely that early Earth had the mix of light elements seen today in the outer part of the solar system.

I agree with this part of your statement too. Whatever process formed the planets, it favored heavy elements for the planets closer to the Sun, and lighter elements in the more distant orbits.


Nobody has reported the presence of "strange" Xe on Earth.
I don't think we need to try and associate this esoteric measurement of Xenon isotope ratios to make the more obvious statements above (about the location of light and heavy elements in the solar system) stronger.

om@umr.edu
2005-May-19, 01:45 PM
Originally posted by antoniseb@May 14 2005, 02:00 PM

Nobody has reported the presence of "strange" Xe on Earth.
I don't think we need to try and associate this esoteric measurement of Xenon isotope ratios to make the more obvious statements above (about the location of light and heavy elements in the solar system) stronger.
There nothing esoteric about "tracer isotopes" - a powerful tool for deciphering processes that occur in the laboratory, as well as those that occurred in forming the planets.

"Tracer isotopes" were acknowledged by the Nobel Committee over 60 years ago.

GEORGE DE HEVESY (1885-1966), Professor of Chemistry at the University of Friberg, discovered element #72, Hafnium, and received the Nobel Prize in Chemistry in 1943 for his work on the use of isotopes as tracers in the study of chemical processes.

Let me explain what "tracer isotopes" tell us about the formation of the planetary system.

a.) The inner part of the solar system was rich in heavy elements like Fe, O, Ni, S, and S.

b.) The outer part of the solar system was rich in light elements like H, He, C and N.

Xenon in b.) the outer part of the solar system had twice as much Xe-136 as xenon in a.) the inner part of the solar system.

This xenon "tracer isotope" permits us to conclude with some degree of confidence that the early Earth never had the mix of light elements seen today in the outer part of the solar system.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-19, 02:04 PM
Originally posted by om@umr.edu@May 19 2005, 01:45 PM
a.) The inner part of the solar system was rich in heavy elements like* Fe, O, Ni, S, and S.

b.) The outer part of the solar system was rich in light elements like H, He, C and N.


These two statements are true, regardless of the Xe isotope abundances.


Xenon in b.) the outer part of the solar system had twice as much Xe-136 as xenon in a.) the inner part of the solar system.

This xenon "tracer isotope" permits us to conclude with some degree of confidence that the early Earth never had the mix of light elements seen today in the outer part of the solar system.

(I bolded the word never above). Note that even IF we accept the relationship connecting Xenon abundances to current element abundances, we CANNOT say that there was no process that ever changed the abundances in the inner solar system (such as heat driving away the lighter elements in the early inner solar system). So, you are not permitted to conclude that the Early Earth NEVER had the mix.

That being said, I side with you somewhat and think that writers who compare Titan's atmosphere to that of early Earth are being incautious by implying too many comparisons, and too complete a comparison. There probably are some ways that they were similar, but it is crazy to suggest that Titan is a corbon copy of an Early Earth that was kept on ice for 4.6 billion years, and that if we just thaw it out, we'll have another friendly Earth with a cool view of Saturn's beautiful rings. The writers don't exactly say this, but people seem to read it that way.

om@umr.edu
2005-May-19, 02:32 PM
Originally posted by antoniseb@May 19 2005, 02:04 PM
Note that even IF we accept the relationship connecting Xenon abundances to current element abundances, we CANNOT say that there was no process that ever changed the abundances in the inner solar system (such as heat driving away the lighter elements in the early inner solar system). So, you are not permitted to conclude that the Early Earth NEVER had the mix.


Thanks for your comment.

I apparently failed to explain "tracer isotopes".

How would "heat driving away the lighter elements in the early inner solar system" change "STRANGE XENON" into "NORMAL XENON"?

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-19, 03:22 PM
Originally posted by om@umr.edu@May 19 2005, 02:32 PM
How would "heat driving away the lighter elements in the early inner solar system" change "STRANGE XENON" into "NORMAL XENON"?
It wouldn't. I am saying that the distribution of the various Xenon isotopes can be regarded as a function of the distance from the Sun. The connection to light vs. heavy element abundances is simply that that too is currently a function of the distance from the Sun, and that the mapping of one to the other is not because they always travel together. Another thing that changes with distance from the Sun is dust temperature (for example). You could perhaps just as easily tie the Xenon isotope abundances to that as a tracer, rather than to light vs. heavy elements. The distribution of element abundances of the Early Solar System does not have to have been the same as it is today, as your post implies.

om@umr.edu
2005-May-19, 04:10 PM
Originally posted by antoniseb+May 19 2005, 03:22 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (antoniseb &#064; May 19 2005, 03:22 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-om@umr.edu@May 19 2005, 02:32 PM
How would "heat driving away the lighter elements in the early inner solar system" change "STRANGE XENON" into "NORMAL XENON"?
It wouldn&#39;t. I am saying that the distribution of the various Xenon isotopes can be regarded as a function of the distance from the Sun. . . . . The distribution of element abundances of the Early Solar System does not have to have been the same as it is today, as your post implies. [/b][/quote]
Obviously I failed to explain "tracer isotopes".

The distribution of elements in the Early Solar System does have to be the same as that in the supernova that produced them.

a.) "NORMAL XENON" came from the interior of the supernova where heavy elements like Fe, O, Si and S were abundant.

b.) "STRANGE XENON" (with excess isotopes from the r- and p-processes of nucleosynthesis) was made in the outer part of the supernova where light elements like H, He, C and N were abundant.

If a.) ever mixed with b.), no known process could separate the elements and also separate "NORMAL XENON" from "STRANGE XENON" to reproduce the present observation :

a.) "NORMAL XENON" is today linked with heavy elements like Fe, O, Si and S.

b.) "STRANGE XENON" is today linked with light elements like H, He, C and N.

I regret that I am unable to communicate more clearly about the merits of "tracer isotopes" - a powerful tool for deciphering processes that occurred in forming the solar system.

Perhaps the 1943 Nobel Prize lecture by GEORGE DE HEVESY would explain this better.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-19, 04:23 PM
Originally posted by om@umr.edu@May 19 2005, 04:10 PM
a.) "NORMAL XENON" came from the interior of the supernova where heavy elements like Fe, O, Si and S were abundant.

b.) "STRANGE XENON" (with excess isotopes from the r- and p-processes of nucleosynthesis) was made in the outer part of the supernova where light elements like H, He, C and N were abundant.
Here you presume that the Sun is a remnant core of a Supernova that exploded with insufficient force to blow these materials out of it&#39;s gravitational grip. This is not a serious explanation for the nature of the solar system, but your presumption of it explains why you are maintaining that the element abundances near the Earth couldn&#39;t have changed since the early days of the Solar System. Please confine these very non-standard ideas to the Alternative Theories section.

om@umr.edu
2005-May-19, 04:24 PM
No, Anton.

The observations do not "presume that the Sun is a remnant core of a Supernova".

Observations are observations &#33;

Please see the Nobel lecture by Theodore W. Richards on December 6, 1919:

"If our inconceivably ancient Universe even had any beginning, the conditions determining that beginning must even now be engraved in the atomic weights.

They are the hieroglyphics which tell in a language of their own the story of the birth or evolution of all matter, and the Periodic Table containing the classification of the elements is the Rosetta Stone which may enable us to interpret them.

Until, however, these hieroglyphics are clearly visible in their true form, we cannot hope for an interpretation.

The first task of the investigator is to define sharply the outlines of these graven characters, in order that their true form may be manifest.

Then perhaps there is hope of deciphering their meaning.

See page 282 of T. W. Richards in Nobel Lectures, Chemistry, 1914 (published for the Nobel Foundation by Elsevier Publishing Co, Amsterdam) pp. 280-292 (1966).

This explains why mass spectrometers are used to try to decipher the origin of the elements and the formation of the solar system.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-19, 04:27 PM
Originally posted by om@umr.edu@May 19 2005, 04:24 PM
This explains why mass spectrometers are used to try to decipher the origin of the elements and the formation of the solar system.
I&#39;ve never doubted the importance of these studies. What is in doubt are your interperetations and conclusions.

om@umr.edu
2005-May-19, 04:43 PM
Originally posted by antoniseb+May 19 2005, 04:27 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (antoniseb @ May 19 2005, 04:27 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-om@umr.edu@May 19 2005, 04:24 PM
This explains why mass spectrometers are used to try to decipher the origin of the elements and the formation of the solar system.
What is in doubt are your interperetations and conclusions. [/b][/quote]
Sorry, Anton.

I do not want to be confrontational, but

"Observations are observations &#33;"

I said nothing about the Sun.

"Tracer isotopes" falsify your interperetation of the "observations".

As noted above,

If a.) ever mixed with b.), no known process could separate the elements and also separate "NORMAL XENON" from "STRANGE XENON" to reproduce the present observations:

a.) "NORMAL XENON" is today linked with heavy elements like Fe, O, Si and S.

b.) "STRANGE XENON" is today linked with light elements like H, He, C and N.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-19, 05:06 PM
Originally posted by om@umr.edu@May 19 2005, 04:43 PM
"Tracer isotopes" falsify your interperetation of the "observations".
Really, how do they do that?

If a.) ever mixed with b.), no known process could separate the elements and also separate "NORMAL XENON" from "STRANGE XENON" to reproduce the present observations

Your normal (i.e. terrestrial) Xenon is here with whatever is here now. It was here with whatever was here then. Your claim that nothing could have changed the elemental abundance ratios on the terrestrial planets is wrong, and unrelated to what might have changed (or not changed) the isotope abundance ratios of Xenon in the same environment.

If for example, the Early Earth had a huge amount of Methane and Ammonia in its atmosphere, and much of this was blown into interplanetary space by the collision that formed the moon, leaving behind heavier gasses such as Nitrogen, Oxygen, Argon, and Carbon-dioxide, that might have evaporated away some Xenon too, but it wouldn&#39;t have changed the Xenon isotope ratio here.

Likewise, Venus may previously had a great deal more Hydrogen (as H2, Water, Methane, Ammonia, or what-have-you, but the heat of that planet may over the years have driven most of it away, resulting in a much elevated Deuterium ratio on that planet.

Both of these are probably situations for the evolution of our solar system to where we are now that would have changed the element abundances, but not alterered the Xenon isotope ratio substantially.

om@umr.edu
2005-May-20, 03:52 AM
Originally posted by antoniseb+May 19 2005, 05:06 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (antoniseb @ May 19 2005, 05:06 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-om@umr.edu@May 19 2005, 04:43 PM
"Tracer isotopes" falsify your interperetation of the "observations".
Really, how do they do that?
[/b][/quote]
"Tracer isotopes" are like dyes.

"NORMAL XENON" (from the inner part of the solar system) is like BLUE DYE.

"STRANGE XENON" (from the outer part of the solar system) is like RED DYE.

If elements from the inner and outer parts of the solar system ever mixed, driving light elements away from the inner solar system would not separate the two dyes.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-20, 12:57 PM
Originally posted by om@umr.edu@May 20 2005, 03:52 AM
If elements from the inner and outer parts of the solar system ever mixed, driving light elements away from the inner solar system would not separate the two dyes.
You didn&#39;t address the two scenarios I posted above. In both cases the element abundance of the terrestrial planet changes (reducing the light elements), but the Xenon isotope ratio doesn&#39;t change. Further, since the material lost by the terrestrial planet goes out away from the sun in a diffuse fashion, it does not substantially contaminate the outer planets&#39; ratios.

So your statement that the Xenon is proof that the element abundance ratios are the same now as always is false, and your claim for the use of Xenon as a tracer is over-reached. (No doubt it does trace SOMETHING, but obviously not everything you claim).

John L
2005-May-20, 01:51 PM
I think you&#39;re both assuming too much about the outer planets. We know what the upper atmospheres of those worlds are made of, but we know nothing of what their cores are made. We can only infer the composition of the Earth&#39;s core at that. So talking about the relative abundance of elements in the solar system is not so simple a matter.

om@umr.edu
2005-May-20, 02:14 PM
John is right.

We only know about material at the surface of the Earth, the Sun, Mars, and Jupiter.

But "tracer isotopes" unambiguously tell us the material at the surface of Jupiter never mixed with the material that we see at the surface of Earth, Mars and the Sun.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-20, 03:07 PM
Originally posted by om@umr.edu@May 20 2005, 02:14 PM
But "tracer isotopes" unambiguously tell us the material at the surface of Jupiter never mixed with the material that we see at the surface of Earth, Mars and the Sun.
First, this is a much weaker statement than your earlier claim that the tracers show that the Earth&#39;s elemental abundances are the same now as they were when it formed.

Second, I&#39;m not claiming that Jupiter had major mixing from Earth materials, but even so, we do not know what the primative Xenon isotope abundances were. It could be that in the past, the Xenon out there was even "stranger", and that the ratios are slightly closer now to terrestrial values from some minor mixing. Since the Xenon in Jupiter&#39;s atmosphere is in gaseous form, it should be pretty well mixed together, so how could you know?

You keep making these ridiculous claims about what the Xenon can tell us. I agree that it tells us something, but your claims do NOT make physical sense.

UABILL
2005-May-20, 04:12 PM
i like cookies :ph34r:

I titan is a rather interesting place, i hear the surface is a sponge like. Wonder what a little heat would do to this moon It would be very interesting to see. Also i wonder how much its core is cooled off. It would be really neat of they found vulcanism on the planet, that could really jump start things. At least i think, i fear even talking sometimes on these boards because some super nerds goin to jump down my throat about how i failed to explain the structure of a quark or some shiii...

lets hear it&#33;

antoniseb
2005-May-20, 05:10 PM
Originally posted by UABILL@May 20 2005, 04:12 PM
i fear even talking sometimes on these boards because some super nerds goin to jump down my throat about how i failed to explain the structure of a quark or some shiii...

Usually the intensity of the jump down your throat is proportional to how well you make a wrong idea sound like an established fact. If all you do is speculate, or ask questions, or explain things well, you&#39;ll usually get treated in a friendly helpful manner. Alternative ideas DO have a place on this forum down in the alternative theories section, but not up here in the News sections.


titan is a rather interesting place, i hear the surface is a sponge like
It might be more like the surface of a "Slushy" drink, but a sponge night also describe it.

It would be really neat of they found vulcanism on the planet, that could really jump start things.
There might well be some kind of Cryovulcanism going on, where the "lava" is still colder than the freezing point of water. Titan&#39;s surface is made of things that are gases and liquids at temperatures and pressures we are used to. But it is relatively close to Saturn, and probably does get some tidal heating going on, and may still have a warm core inside it.

om@umr.edu
2005-May-20, 06:53 PM
Originally posted by antoniseb@May 20 2005, 03:07 PM
You keep making these ridiculous claims about what the Xenon can tell us. I agree that it tells us something, but your claims do NOT make physical sense.
I am obviously unable to communicate to Anton:

a.) "NORMAL XENON" is linked with heavy elements like Fe, O, Si and S, in rocky planets like Earth and Mars and in tiny meteorite inclusions from the birth of the solar system.

b.) "STRANGE XENON" is linked with light elements like H, He, C and N, in gaseous planets like Jupiter and in tiny meteorite inclusions from the birth of the solar system.

If a.) ever mixed with b.), no known process could separate the elements and also separate "NORMAL XENON" from "STRANGE XENON" to reproduce these observations.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-20, 07:09 PM
Originally posted by om@umr.edu@May 20 2005, 06:53 PM
I am obviously unable to communicate to Anton
Look, I don&#39;t want this escalating into some sort of personal flame war. The fact is I&#39;ve made some good points, and you aren&#39;t addressing them. If you want to go on saying that I&#39;m impossible to communicate with go ahead, but I think I&#39;ve made my point, and your attacks do not include any rebuttle.

Duane
2005-May-20, 07:37 PM
A quick reply. Dr O, you use an assumption that the so called "normal" xenon mixed with the "strange" xenon. In this you may be incorrect.

At it&#39;s beginning the cloud of gas which collapsed to form the sun and solar system was subjected to several episodes of material injection arising from Type I and II supernovas, material from Wolfe-Rayet stars, and material from Red Giants. Furthermore, once the sun had ignited, the system was subjected to additional added material resulting from nearby supernovas, and material from the Wolfe-Rayet phase of the precursor supernova stars.

Additonally, during the T-Tauri phase of it&#39;s development, the sun was actually casting off accreting material in the form of jets.

It may be that "strange" xenon was added to the outer regions after the dust cloud making up the proto-solar system had already condensed to the point where it could not penetrate to the center, or was added after the ignition of the sun, or was preferencially swept out of the inner region by the action of the T-Tauri stage jets.

It is certainly the case that the ignition of the proto-sun, combined with the action of the jets arising during its T-Tauri phase, would have swept the inner solar system clear of the lighter elements. As such, xenon associated with heavy elements could have been retained whereas xenon associated with lighter elements could have been swept away.

SO there are at least three methods by which the xenon levels could have been altered in the solar system.

Of course, this has been brought to your attention before.