Liquid water not needed.

SkyandTelescope wrote:When Hörst and her team analyzed the experiment's byproducts, they discovered a trove of organic molecules critical to the existence of life. Among them were adenine, cytosine, guanine, thymine, and uracil — the five key nucleotide compounds found in DNA and RNA — along with a dozen amino acids.

http://www.skyandtelescope.com/community/skyblog/newsblog/104579744.html

Interesting. Hopefully they're right about this:

But careful checks prove that these compounds were synthesized in the experiment, rather than being contaminants from inhabitants of Planet Earth.

Titan did it!

Ah, but that only proves that these compounds can be produced when humans artificially recreate the conditions of Titan. It doesn't show that these compounds can form when the conditions present on Titan occur naturally. So it isn't proof you can make these compounds without the intervention of an Intelligent Agent(TM).

There's that out of the way.

The uracil is interesting given that "codons of very hydrophobic amino acids, highly represented in integral membrane proteins, are composed of 50% uracils..." (ref: Studying membrane proteins through the eyes of the genetic code revealed a strong uracil bias in their coding mRNAs, (Jaime Priluskya and Eitan Bibi), liquid water may not be essential to form the building blocks but without the presence of water to force polar molecules to orient themselves and thus in the end form membranes - you will not get on the path to the next steps which get us to membranes (and cells).

This is excellent news that it confirms we don't need liquid water or the right surfaces to get the building blocks. We only (probably) need the water and (probably) surfaces to get the next steps towards cells.

This is extremely interesting, but it raises another important question : Does the same chemistry allow for the formation of ribose and the subsequent joining of the bases with it?

Though I must say, the formation of all five bases from the same chemistry, even in the absense of ribose is incredible.
I would love to read the paper on the experiment. Anyone know where to find it?

Arcanyn wrote:Ah, but that only proves that these compounds can be produced when humans artificially recreate the conditions of Titan. It doesn't show that these compounds can form when the conditions present on Titan occur naturally. So it isn't proof you can make these compounds without the intervention of an Intelligent Agent(TM).

There's that out of the way.

Dealt with that canard when the duplicitous Dunsapy erected it over at RDF, and tried to claim that laboratory experiments in abiogenesis support creation by an intelligence. The operation of natural processes, and the experiments required to learn about their operation, are two different entities. Likewise, real world observational phenomena, and the theories erected to explain them, are also two different entities.

The only intelligence involved was in the setting up of the experiment. The molecules were left to react, or not react, in accordance with the appropriate physical and chemical laws. The scientists weren't bolting the molecules together individually Lego fashion, they were simply sitting there watching the experimental setup, to see if the appropriate chemical reactions would or would not take place.

Indeed, I've seen this specious apologetic excrement being erected on numerous occasions by reality denialists and mythology fetishists, and its equally specious converse. On the one hand, if an experiment fails to produce the required chemical product, creationists claim that this "proves" that an invisible magic man was needed. On the other hand, if an experiment does produce the required chemical product, they claim that this "proves" that an invisible magic man was still needed, because the chemicals wouldn't have done this if they hadn't been put together by the intelligence of the scientists. Which of course is complete poppycock, as I've just explained in the previous paragraph.

Claiming that this somehow validates the need for an invisible magic man is like saying that because scientists perform experiments dropping things from towers in order to learn about gravity, gravity needs an invisible magic man to make it work.

Now that I've dealt with that bullshit, let's return to the interesting science shall we, and leave mythology-based bullshit out of this thread?

EDIT : No, it's just the abstract

http://meetingorganizer.copernicus.org/EPSC2010/EPSC2010-219.pdf

Title:
Formation Of Amino Acids And Nucleotide Bases In A Titan Atmosphere Simulation Experiment
Authors:
Horst, Sarah; Yelle, R. V.; Buch, A.; Carrasco, N.; Cernogora, G.; Dutuit, O.; Quirico, E.; Sciamma-O'Brien, E.; Smith, M. A.; Somogyi, A.; Szopa, C.; Thissen, R.; Vuitton, V.

Abstract
Titan has been a subject of astrobiological interest since the Voyager spacecraft first revealed the diversity of the organic chemistry occurring in the atmosphere. However, it was not until the arrival of Cassini-Huygens that the chemical complexity of Titan's atmosphere was fully appreciated. The Cassini Plasma Spectrometer (CAPS) observed negative ions with m/z values up to 10,000 u/q at 950 km [1] and positive ions with m/z up to 400 u/q [2]. CAPS has also observed O+ flowing into Titan's atmosphere [3]. While Titan's atmosphere is relatively oxygen poor compared to terrestrial planets, CO is the fourth most abundant molecule in the atmosphere (˜50 ppm). The fact that the observed O+ flux is deposited in the region now known to contain large organic molecules leads to the exciting possibility that oxygen can be incorporated into these molecules resulting in the production of prebiotic molecules.
In this work, Titan aerosol analogues (or "tholins") produced in PAMPRE, a Titan atmosphere simulation experiment, have been analyzed in a very high resolution LTQ Orbitrap mass spectrometer. These PAMPRE tholins were produced by capacitively coupled RF discharge in a mixture of N2, CH4 and CO. The tholins were found to contain 18 molecules with molecular formulae corresponding to biological amino acids and nucleotide bases. GC-MS measurements have confirmed the structure of seven: adenine, cytosine, uracil, thymine, guanine, glycine and alanine. The production of prebiotic molecules under atmospheric conditions presents a new source of prebiotic material and may increase the range of planets where life could begin.

Actually, what you found was the abstract. The full paper is published in Bulletin of the American Astronomical Society, vol 42, p.1068. Sadly, it's institutional access only at the moment, unless someone knows of an alternative source ...

EDIT: I found a second paper. This one can be downloaded freely from arXiv.

I asked Carolyn Porco, Neil Tyson and Ananyo Bhattacharya for the full article. Slim chances of their responding though.

Calilasseia wrote:Actually, what you found was the abstract. The full paper is published in Bulletin of the American Astronomical Society, vol 42, p.1068. Sadly, it's institutional access only at the moment, unless someone knows of an alternative source ...

EDIT: I found a second paper. This one can be downloaded freely from arXiv.

Thx cali. Not the exact same experiment though. In the one you linked they used X-rays and in the other Radiofrequency, and in the one you linked they only succeeded in producing Adenine. That's the thing that makes the new experiment so interesting, they got all five nucleobases in addition to some amino acids, and they only succeeded in identifying 7 of 18 total compounds produced.
This is pure speculation of course, but Imagine if the same or other plausible condidtions on Titan allow for the subsequent formation of Ribose and joining it to the base? We'd get RNA monomers. In all the experiments I have read about in prebiotic chemistry, they only produced one or two of the nucleobases, never all five.

I found an old one

http://meetingorganizer.copernicus.org/ ... 10-418.pdf

http://astrobiology.gsfc.nasa.gov/pdf/1 ... l_1999.pdf

According to Neil, "RT @neiltyson: @natselrox Story reported on a presentation at a scientific conference. It's not yet an e-mailable published paper."

Carolyn Porco: RT @carolynporco: @natselrox I don't have the article myself.