Origin of organic molecule in space?

[TemperateSeaIsland]

What is the density of gases in an area of a nebula where it is far away from a new star? Either the chance of the formation of an organic molecule is slim, or the chance of the preservation of the organic molecule is slim. If we released a CH4 molecule into the space between earth and moon, how long could it survive? My guess is about ... a month?

I think organic molecules might even have hard time to be preserved in the conditions of primordial earth. Needless to say anywhere else in the space (nebula).

In a vacuum around Earth methane would likely form a free radical (CH3.) and after that it wont do much until it would interact with another molecule. For example if it encountered another methyl radical it would form ethane.

 

[juvenissun]

In a vacuum around Earth methane would likely form a free radical (CH3.) and after that it wont do much until it would interact with another molecule. For example if it encountered another methyl radical it would form ethane.

How would the CH4 behave when it is farther away from the earth? Would it eventually become ions of H and C?

Has anyone tested the rate of CH4 dissociation by radiation (say UV light) in a lab setting? I think it should have been done.

 

[juvenissun]

How long is a piece of string? Nebulae vary in density, though generally they're less dense near stars due to gravity and the solar wind.


Ionising radiation would make short work of it, sure, but that's because it would be relatively close to the Earth, the Moon, and the Sun, and wouldn't be shielded from radiation by a large quantity of gas. Besides, it's not universally true that radiation always denatures organic molecules into their constituent atoms - usually it'll be basal atoms, such as methane or ammonia. And even then, cosmic rays can help synthesise more complex molecules by providing that extra influx of energy.


Why would they have a hard time being preserved in primordial Earth?

There is no reason for organic molecules be formed on comets and asteroids. They are small and cold and give no protection to their surface material. Yet we found large organic molecules near the surface of comet (blown off particles). Where did they come from? If a random sampling on comet dust showed organic molecules, does that suggest that comet is full of organic material? Was comet a lump of water vapor in space and was small ice particles and dust in the early solar system? If so, all possible organic material should be disintegrated by the solar wind before the ice and dust condensed into a comet.

(I should come back to the conditions of primordial earth later.)

 

[Wiccan_Child]

There is no reason for organic molecules be formed on comets and asteroids. They are small and cold and give no protection to their surface material.

On the contrary, as I explained earlier, comets can be quite warm given the right conditions (atmospheric skipping, proximity to a star, etc), and are full of the right materials (water, carbon, hydrogen, etc).

Yet we found large organic molecules near the surface of comet (blown off particles). Where did they come from? If a random sampling on comet dust showed organic molecules, does that suggest that comet is full of organic material? Was comet a lump of water vapor in space and was small ice particles and dust in the early solar system? If so, all possible organic material should be disintegrated by the solar wind before the ice and dust condensed into a comet.

Not really. As I said earlier, cosmic rays are known to catalyse the formation of organic materials, given the right conditions. Simple molecules like methane or ammonia are quite hardy when not in free space. Meteors, flying through the solar system, would pick up all the debris from the primordial stellar dust cloud - which would include organic material. So, even if meteors can't synthesise their own material (and there's no reason why they couldn't), nebular material could simply deposit on the rocks that fall to Earth.

As for meteors themselves, again, organic molecules in space form piecemeal, rather than atom-by-atom. Once you have the sturdier basal molecules, it's trivial for those to combine into more complex molecules like amino acids. Despite your assertion to the contrary, meteors do provide shielding from radiation - molecules both inside the meteor and those on its 'dark' side relative to the radiation source. When exposed to light, they simply evaporate into dust, rather than denature into the constituent molecules.

In molecular clouds, where molecules aren't generally stuck to rock, UV light can catalyse the formation of more complex molecules, such as glycine. We can replicate the conditions of interstellar dust clouds here on Earth, and we have found that such conditions for even more complex molecules than we have thus far found in real nebulae - including three amino acids, glycine, alanine, and serine.

(I should come back to the conditions of primordial earth later.)

Very well.

 

[juvenissun]

On the contrary, as I explained earlier, comets can be quite warm given the right conditions (atmospheric skipping, proximity to a star, etc), and are full of the right materials (water, carbon, hydrogen, etc).


Not really. As I said earlier, cosmic rays are known to catalyse the formation of organic materials, given the right conditions. Simple molecules like methane or ammonia are quite hardy when not in free space. Meteors, flying through the solar system, would pick up all the debris from the primordial stellar dust cloud - which would include organic material. So, even if meteors can't synthesise their own material (and there's no reason why they couldn't), nebular material could simply deposit on the rocks that fall to Earth.

As for meteors themselves, again, organic molecules in space form piecemeal, rather than atom-by-atom. Once you have the sturdier basal molecules, it's trivial for those to combine into more complex molecules like amino acids. Despite your assertion to the contrary, meteors do provide shielding from radiation - molecules both inside the meteor and those on its 'dark' side relative to the radiation source. When exposed to light, they simply evaporate into dust, rather than denature into the constituent molecules.

In molecular clouds, where molecules aren't generally stuck to rock, UV light can catalyse the formation of more complex molecules, such as glycine. We can replicate the conditions of interstellar dust clouds here on Earth, and we have found that such conditions for even more complex molecules than we have thus far found in real nebulae - including three amino acids, glycine, alanine, and serine.


Very well.

You avoid the argument that the synthesis of organic molecules has a very low probability, but the deterioration of existing organic molecules has a very high probability. There is simply no match between these two rates and resulted in any preservation of rare organic substance in space environment.

Yet the fact is: organic molecules in space are pretty common.

The question is not on the formation of organic material, but on the preservation of it.

Take a look of one thing: when a free amino acid molecule (less stable than CH4) floats in space, how long could it exist before been disintegrated by cosmic rays, say at a distance from our sun to the Kuiper Belt. I say that it should be very fast. May be a few earth-days.

Some how, I think this test is very feasible for people on the space station. I guess the information must exist. ... Well, it took me 3 minutes to locate this one. And it sort of confirmed my speculation.

 

[TemperateSeaIsland]

How would the CH4 behave when it is farther away from the earth? Would it eventually become ions of H and C?

Distance from the Earth isnt really an issue. To form something like :C: you would need a very energetic environment. Methane would likely give you CH3, CH2, CH and some C if the you have enough radiation. Generation of Ethane through the mechanism I mentioned earlier.

Has anyone tested the rate of CH4 dissociation by radiation (say UV light) in a lab setting? I think it should have been done.

I have looked but most papers look at mimicking planetary atmospheres so not really ideal for your question. I did find one that looked at methan under UV in a vacuum but forgot to bookmark and I cant find the darn thing now.


As for the paper you posted, it's quite interesting but for some reason they dont mention aa being formed and replenishing in an intersteller medium. Studies have shown that aa can form from water, ammonia, cyanide, alcohols etc.... in the presence of UV.

http://www.astrochemistry.org/docs/2007AminoAcidpaper-ApJ.pdf

Interestingly the paper above mentions a number of pathways but alone they dont fully explain all the observations so there are likely more pathways to form aa.

You avoid the argument that the synthesis of organic molecules has a very low probability

Really? Can you show this is the case?

Where do you think organic molecules such as aa come from?

 

[juvenissun]

Distance from the Earth isnt really an issue. To form something like :C: you would need a very energetic environment. Methane would likely give you CH3, CH2, CH and some C if the you have enough radiation. Generation of Ethane through the mechanism I mentioned earlier.

I have looked but most papers look at mimicking planetary atmospheres so not really ideal for your question. I did find one that looked at methan under UV in a vacuum but forgot to bookmark and I cant find the darn thing now.


As for the paper you posted, it's quite interesting but for some reason they dont mention aa being formed and replenishing in an intersteller medium. Studies have shown that aa can form from water, ammonia, cyanide, alcohols etc.... in the presence of UV.

http://www.astrochemistry.org/docs/2007AminoAcidpaper-ApJ.pdf

Interestingly the paper above mentions a number of pathways but alone they dont fully explain all the observations so there are likely more pathways to form aa.

Really? Can you show this is the case?

Where do you think organic molecules such as aa come from?

I understand the argument on the formation of organic molecules. It takes energy and the energy could be provided by the cosmic radiation, which would in turn, destroy the molecule after its formation. My argument is that we can not only look at one side of the story without evaluating the other side. In a space environment such as in a nebula, destroying an organic molecule is much easier than the formation of it.

So once an organic molecule is made, it needs to be protected from being destroyed again. This would need an environment change, such as move the organic molecule to a gas cloud of higher density. So this is a race between the rate of molecule formation and the rate of environmental change. The major problem is that I can not see how could this mechanism of protection work at a pace faster enough in a non-planetary environment. My problem is not on the formation of organic molecules in a lab setting, not even in a primordial planet, but on small objects like comet or asteroid.

My idea on the common occurrence of organic molecule in space is a logic one, rather than a scientific one. So, I like to satisfy myself on a scientific understanding: it is not likely to preserve an organic molecule such as an amino acid on a comet.

 

[Orogeny]

In a space environment such as in a nebula, destroying an organic molecule is much easier than the formation of it.

You continue to make this assertion without providing evidence for its validity. Provide that evidence now.

 

[juvenissun]

You continue to make this assertion without providing evidence for its validity. Provide that evidence now.

What do you think about the assertion? No idea?

 

[Tiberius]

Organic molecules are just molecules that contain carbon.

 

[Orogeny]

What do you think about the assertion? No idea?

I think your assertion holds no weight until you back it with evidence. Please do this now.

 

[juvenissun]

I think your assertion holds no weight until you back it with evidence. Please do this now.

What is wrong with my assertion?
If you do not know what is wrong, what would the evidence be used for?

 

[CabVet]

I understand the argument on the formation of organic molecules. It takes energy and the energy could be provided by the cosmic radiation, which would in turn, destroy the molecule after its formation. My argument is that we can not only look at one side of the story without evaluating the other side. In a space environment such as in a nebula, destroying an organic molecule is much easier than the formation of it.

If there are things being formed and destroyed in space all the time, you would think you would find some of them, wouldn't you? Even if they had a short life cycle? A lightning bolt lasts for only a split-second, yet I am sure you saw one before, with your very eyes. Want another analogy? Sand castles are much harder to build than to destroy, but if you walk along a beach in a weekend, you will very likely see one. The fact that it is easier to destroy a molecule than it is to make it has no influence in our ability to detect such molecules.

 

[thaumaturgy]

Why out of place? They're just chemicals.

"just chemicals" you say?

Not this organic molecule:

This molecule brings me LIFE! It raises me from the dead! All praise!

This molecule is so powerful that ONLY A GOD could have made it! And He made it for ME! Why? Because HE LOVES ME.

God so loved the world that He gave his only be...hey, wait! gimme that...I WASN'T DONE WITH IT! Give it back, &^%$#@# barrista! I'll show you... GIVE.THAT.BACK! Wait! This place is the only place with free wifi...NO! I"M NOT GOING TO LEAVE.....NO. GIve that back to ME. GIMME IT!

Oh great, yeah "Call the cops" I can yell in a STARBUCKS IF I WANT. Now give me back that...what? What did you say...?

 

[Orogeny]

What is wrong with my assertion?
If you do not know what is wrong, what would the evidence be used for?

The primary thing that is wrong with your assertion is that you've provided no evidence regarding its validity. Please do so now. The evidence will either confirm or refute its validity. Why is this so difficult to understand?

 

[juvenissun]

If there are things being formed and destroyed in space all the time, you would think you would find some of them, wouldn't you? Even if they had a short life cycle? A lightning bolt lasts for only a split-second, yet I am sure you saw one before, with your very eyes. Want another analogy? Sand castles are much harder to build than to destroy, but if you walk along a beach in a weekend, you will very likely see one. The fact that it is easier to destroy a molecule than it is to make it has no influence in our ability to detect such molecules.

So, tell me your imagination that how would an organic molecule be preserved on a comet. I don't need evidence, I just want to hear your reasonable speculation.

 

[CabVet]

So, tell me your imagination that how would an organic molecule be preserved on a comet. I don't need evidence, I just want to hear your reasonable speculation.

It doesn't need to be preserved, it just needs to form often enough that it is detectable.

 

[Tiberius]

So, tell me your imagination that how would an organic molecule be preserved on a comet. I don't need evidence, I just want to hear your reasonable speculation.

Do you know of some mechanism that exists on comets that would destroy molecules containing carbon but not those that don't contain carbon?

 

[thaumaturgy]

A key thing to remember is that while the term "organic chemicals" once meant that we thought they were formed by life, this is not the case any more. Some, many, organic chemicals are indeed formed by living things, but many, many, many, many (a huge many) organic molecules can by synthesized through wholly "non-biotic" means.

Here's a few examples:

First there's this:

Simulation experiments on ground have shown that “amino acid precursors”, which give amino acids after acid-hydrolysis, can be formed when an ice mixture simulating ice mantles of interstellar dust particles (ISDs) is irradiated with high energy particles or UV light. (SOURCE)

Then...

Glycine was produced in a solution of 2-aminoethanol, methylamine, ethylamine, or acetonitrile by UV-irradiation. The concentrations of the reactants and glycine were analyzed under six different conditions. Each reaction was assumed to be a first-order reaction. (SOURCE)

Glycine is an amino acid. Now granted in this study further exposure to the UV could cause some breakdown of the Glycine, but we see the ability to take simpler compounds and through the use of UV form complex things like amino acids.

During cosmic time, many galaxies undergo intense periods of star formation, during which heavy elements like carbon, oxygen, nitrogen, silicon and iron are produced. Also, many complex molecules, from carbon monoxide to polycyclic aromatic hydrocarbons, are detected in these systems, like they are for our own Galaxy. Interstellar molecular clouds and circumstellar envelopes are factories of complex molecular synthesis. A surprisingly high number of molecules that are used in contemporary biochemistry on the Earth are found in the interstellar medium, planetary atmospheres and surfaces, comets, asteroids and meteorites and interplanetary dust particles. (SOURCE)

There is little "mysterious" here, the chemistry is not out of the bounds of science. If one wants to see mystery in this sort of thing, then one most assuredly can, but it seems hardly mysterious (kind of like that whole thing about upright tree fossils in Nova Scotia).

MIller and Urey in 1953 carried out the "abiotic" production of amino acids using electrical discharge

(SOURCE)

The ability to form organic compounds, even amino acids. Some of the key factors are to maintain a relatively "reducing" environment so it doesn't oxidize away. Since Millery-Urey in the 1950's all 20 amino acids have been thus synthesized along with ATP, some sugars, lipids and a couple bases found in RNA and DNA. (SOURCE)

Several abiotic reaction mechanisms are proposed here for sugars and amino acids etc. (LINKY)

 

[AV1611VET]

MIller and Urey in 1953 carried out the "abiotic" production of amino acids using electrical discharge

That diagram is missing a very key word there, scientist.

Can you find it?

Hint: One little four-letter word found down there where the new diagram says: Amino acids found here.