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A.DIM
2011-Nov-16, 03:24 PM
A few weeks ago "astronomers report(ed) that organic compounds of unexpected complexity exist throughout the Universe. The results suggest that complex organic compounds are not the sole domain of life but can be made naturally by stars."

From PhysOrg (http://www.physorg.com/news/2011-10-astronomers-complex-universe.html) (UT did a story too).

While this supports the idea that life could be widespread, "Theoretically, this is impossible, but observationally we can see it happening."

"The team's discovery suggests that complex organic compounds can be synthesized in space even when no life forms are present."

On Earth, theoretically and observationally, these compounds are the remains of ancient life. Before this discovery it was thought they were produced only by ancient life. So how do they know these compounds aren't the remains of ancient life? Could there not have been inhabited planets around those stars before they went nova and these spectra are showing their remnants and detritus?

JCoyote
2011-Nov-16, 04:10 PM
My only question on that would be one of quantity. The amounts of said organic compounds, and whether they could be reasonably assumed to originate from a planetary source or if there is so much required to make this visible change that it absolutely must be a stellar scale of organic mass.

eburacum45
2011-Nov-16, 05:05 PM
During certain stages of their life cycle, especially (but not only) if they explode as a supernova, some stars kick out vast amounts of carbon, oxygen, nitrogen and hydrogen; organic chemicals form from these materials, in space. The statement that 'stars' make these compounds is only indirectly true. Most stars are far too hot for organic compounds to persist.

John Jaksich
2011-Nov-16, 10:41 PM
A few weeks ago "astronomers report(ed) that organic compounds of unexpected complexity exist throughout the Universe. The results suggest that complex organic compounds are not the sole domain of life but can be made naturally by stars."

From PhysOrg (http://www.physorg.com/news/2011-10-astronomers-complex-universe.html) (UT did a story too).

While this supports the idea that life could be widespread, "Theoretically, this is impossible, but observationally we can see it happening."

"The team's discovery suggests that complex organic compounds can be synthesized in space even when no life forms are present."

On Earth, theoretically and observationally, these compounds are the remains of ancient life. Before this discovery it was thought they were produced only by ancient life. So how do they know these compounds aren't the remains of ancient life? Could there not have been inhabited planets around those stars before they went nova and these spectra are showing their remnants and detritus?

Couple of questions, my friend, how can you prove (or better--what do mean) that complex molecules are the remains of ancient life.

If you examine chemical reactivity---of normal hydrocarbon molecules in space---e.g. PAHs--they are known to (or better to point) produce complex molecules that contain nitrogen and oxygen atoms within their framework--

The reaction route is postulated and published in 2008 which seemingly shows that their existence (by a Taiwanese-led group of Astrophysicists).

I will post the citation in a following post.

John Jaksich
2011-Nov-16, 10:58 PM
Here is the citation which I can not legally post (?)----

Y. -J. Chen et. al.

Amino acids produced from the UV/Extreme-UV irradiation of Naphthalene in a H20 + NH3 ice mixture

Monthly Notices of the Royal Astronomical Society--384, 605-610 (2008)



ADIM--I believe your post but I question some of your interpretations that life started before the chemistry?

It might be possible but---the sheer existence of the cosmic radiation, (including the inducing radiation) makes them unstable within a certain amount of time (of which I am unsure)

That type of question involves a (kinetic aspect to it)---e.g. time of a half life --lets say?

A.DIM
2011-Nov-17, 01:15 PM
My only question on that would be one of quantity. The amounts of said organic compounds, and whether they could be reasonably assumed to originate from a planetary source or if there is so much required to make this visible change that it absolutely must be a stellar scale of organic mass.

Good question.
I imagine the abundance of these complex organics is why the researchers suggest they're made by stars instead of being remains of inhabited planets.

A.DIM
2011-Nov-17, 01:18 PM
During certain stages of their life cycle, especially (but not only) if they explode as a supernova, some stars kick out vast amounts of carbon, oxygen, nitrogen and hydrogen; organic chemicals form from these materials, in space. The statement that 'stars' make these compounds is only indirectly true. Most stars are far too hot for organic compounds to persist.

Right, this is why I wonder why they'd suggest these complex organics are made and spewed out by stars.

A.DIM
2011-Nov-17, 01:25 PM
Couple of questions, my friend, how can you prove (or better--what do mean) that complex molecules are the remains of ancient life.

Hi John.
The chemical signatures are described as resembling those of coal and petroleum, which on Earth are remains of ancient life.


If you examine chemical reactivity---of normal hydrocarbon molecules in space---e.g. PAHs--they are known to (or better to point) produce complex molecules that contain nitrogen and oxygen atoms within their framework-- ...

Yes, this has been the hypothesis ...

For over two decades, the most commonly accepted theory on the origin of these signatures has been that they come from simple organic molecules made of carbon and hydrogen atoms, called polycyclic aromatic hydrocarbon (PAH) molecules. From observations taken by the Infrared Space Observatory and the Spitzer Space Telescope, Kwok and Zhang showed that the astronomical spectra have features that cannot be explained by PAH molecules.

eburacum45
2011-Nov-17, 01:46 PM
Well these kerogen-like materials found in carbonaceous chondrite meteorites have to come from somewhere.
http://www.sciencedirect.com/science/article/pii/S0016703702009821

It seems encouraging that such complex organic compounds are forming in deep space, probably quite soon after the component elements are expelled from the star. I would expect the star itself would supply the energy that is required for this sort of synthesis - so, in many ways, the stars do produce these organic compounds. The synthesis probably occurs near the star, perhaps very near the star, rather than inside it.

Paul Wally
2011-Nov-18, 04:49 PM
I suppose these compounds are formed around very young stars where the star interacts with the surrounding nebulous material? But then I don't understand why we don't observe these complex organics on other planets and moons of our solar system like Mars for instance, or have we observed it there? Or what if the habitable zone coincides with the zone in the nebula where the physical conditions for the formation of these molecules are possible?

AndreH
2011-Nov-18, 04:59 PM
I suppose these compounds are formed around very young stars where the star interacts with the surrounding nebulous material? But then I don't understand why we don't observe these complex organics on other planets and moons of our solar system like Mars for instance, or have we observed it there? Or what if the habitable zone coincides with the zone in the nebula where the physical conditions for the formation of these molecules are possible?

As I understand current theories as mars or earth planets undergo a hot, molten state during formation. Wouldn't that destroy all organic material? Not an expert, though.

Paul Wally
2011-Nov-18, 05:59 PM
As I understand current theories as mars or earth planets undergo a hot, molten state during formation. Wouldn't that destroy all organic material? Not an expert, though.

I suppose after the planets have formed and cooled to form a crust there are still residual materials left in inter-planetary space, and those materials then impact on the cooler planets. I only read the article after writing my post and they say the organics are formed by the supernova star and therefore not by the young stars (I suppose). I don't know how they distinguish between the two possible causes, but it does seem to me that based on what we see in our solar system that the formation is localized to a particular zone. So the supernova explanation doesn't seem right to me. But I'm no expert either.

A.DIM
2011-Nov-18, 08:56 PM
Well these kerogen-like materials found in carbonaceous chondrite meteorites have to come from somewhere.
http://www.sciencedirect.com/science/article/pii/S0016703702009821

Indeed.
And as your article points out, "The prevailing current explanation for the presence of free linear saturated hydrocarbons in carbonaceous meteorites, apart from contamination, is the abiotic route ... " and "The types of the hydrocarbons in meteorites resemble those typical of ancient terrestrial deposits of organic-rich sediments ..." we might consider ancient inhabited planets blown away by these supernovae as a source.


It seems encouraging that such complex organic compounds are forming in deep space, probably quite soon after the component elements are expelled from the star. I would expect the star itself would supply the energy that is required for this sort of synthesis - so, in many ways, the stars do produce these organic compounds. The synthesis probably occurs near the star, perhaps very near the star, rather than inside it.

Whatever the mechanism Kwok deemed it "theoretically impossible," presuming the prevailing current explanation of course.
I like surprises and of course tend towards more biotic explanations, I daresay simpler.

profloater
2011-Nov-18, 09:23 PM
This week's New Scientist carries a story about extraordinary reactions at near zero temperatures, as in space, the lower movement of atoms might allow reactions that are prevented at higher T. This would be a new mode of complex chemistry as atoms (from stars) drift about in vacuum conditions but sometimes bumping into each other and joining where at higher T their velocities would repel each other. Larger molecules might thus be possible.

A.DIM
2011-Nov-18, 09:24 PM
I suppose after the planets have formed and cooled to form a crust there are still residual materials left in inter-planetary space, and those materials then impact on the cooler planets. I only read the article after writing my post and they say the organics are formed by the supernova star and therefore not by the young stars (I suppose). I don't know how they distinguish between the two possible causes, but it does seem to me that based on what we see in our solar system that the formation is localized to a particular zone. So the supernova explanation doesn't seem right to me. But I'm no expert either.

Only after the LHB was the surface of Earth habitable, and it is quickly thereafter life arises. No doubt organic compounds, life's building blocks, were deposited then. And as I understand it, a supernova is thought to have spurred the formation of our solar system. To me, is stands to reason there were planets around that star before it went nova, "ancient terrestrial deposits of organic rich sediments," which were ultimately incorporated into the formation of our system.

Here is a paper on Organic matter in the Solar System: From colors to spectral bands (http://journals.cambridge.org/download.php?file=%2FIAU%2FIAU4_S251%2FS1743921308 021753a.pdf&code=15b32a4aee399ab79ea5704c1f57a0b3) which suggests "organic solid material is a basic and wide-spread component of the surfaces of many outer Solar System bodies."

A.DIM
2011-Nov-18, 09:29 PM
This week's New Scientist carries a story about extraordinary reactions at near zero temperatures, as in space, the lower movement of atoms might allow reactions that are prevented at higher T. This would be a new mode of complex chemistry as atoms (from stars) drift about in vacuum conditions but sometimes bumping into each other and joining where at higher T their velocities would repel each other. Larger molecules might thus be possible.

Heh, I'd think with "quantum oddities" anything's possible!
:D

Paul Wally
2011-Nov-18, 10:48 PM
Only after the LHB was the surface of Earth habitable, and it is quickly thereafter life arises. No doubt organic compounds, life's building blocks, were deposited then. And as I understand it, a supernova is thought to have spurred the formation of our solar system. To me, is stands to reason there were planets around that star before it went nova, "ancient terrestrial deposits of organic rich sediments," which were ultimately incorporated into the formation of our system.


Though it is possible that our carbon compounds could have come from ancient terrestrial planets, this theory doesn't help to explain how the compounds formed in the first place or why it should have arisen there and not simply here.

trinitree88
2011-Nov-28, 06:01 PM
Though it is possible that our carbon compounds could have come from ancient terrestrial planets, this theory doesn't help to explain how the compounds formed in the first place or why it should have arisen there and not simply here.

The strength of chemical bonds varies from a few electron volts to more than 10, but less than 50 ev. Ultraviolet light easily dissociates these and creates free radicals in space which react with lots of ambient material. Eventually all sorts of molecules proliferate and the most stable ones will dominate the products, but in different concentrations at different light levels. p-chem

A.DIM
2011-Dec-05, 02:43 PM
For those interested, here's the Program Schedule for the recent International Conference on Interstellar Dust, Molecules and Chemistry (http://sites.google.com/site/idmc2011/schedule). Kwok, author of the study in the OP, presented his findings as did others their interesting research.

transreality
2011-Dec-05, 09:50 PM
Coal and petroleum represent massively degenerated remnants of life, only because life represents a massive concentration of organic material that under heat and pressure over millions of years breaks down into its simple reactive components. Organic does not mean pertaining to life, or biological in any way, what it means is; containing carbon. Carbon is produced in stars and emitted in supernova, so it should be expected that molecules containing carbon should form in the envelope of such a star; no need to invoke life-bearing planets at all. By complex organic molecules they seem to be referring to aromatics such as benzene rings (http://www.pnas.org/content/108/2/452.full.pdf+html), these form from degeneration of biological matter in coal etc, but they also assemble from carbon and hydrogen starting with ethane which is a simple aliphatic hydrocarbon molecule C2H6. They do this in smoke clouds and many other far less exotic circumstances than a supernova cloud. These also include volcanic activity which is going to be a much more voluminous source than meteorite bombardment on the early earth.