Discussion: Bumpy Dust Makes Molecular Hydrogen

[Fraser]

SUMMARY: The most common element in the Universe is hydrogen, and much of that is molecular hydrogen, where two atoms are bonded together. Scientists have long puzzled over the question of why all this molecular hydrogen is out there in space. Researchers from Ohio State University might have found the answer. They've developed a simulation that shows how molecular hydrogen is more likely to form on interstellar grains of dust which are bumpy, and not smooth.

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[lswinford]

Sounds like the catalytic converters with their platinum coating on acres of tiny rills and valleys of a base surface are used to clean up the pollution in my cars' engine exhaust. Lots of little places for a cleaner chemistry to take place from the exhaust gasses.

So, hydrogen is the most abundant element (as well as the most obviously simple element), but the molecular hydrogen of space needs heavier elements in order to have a table upon which it can do its molecular bonding? When UV light from the sun does its disassociative thing in atmospheric water to generate the ozone and what molecular oxygen is in our atmosphere from non-photosythetic processes, do we have to have dust as a table for the molecular recombination of the single oxygens into the O3 and O2 molecules? So what happens to the freed H2? When the spectrums that determine hydroxyl molecules in space (OH) by their distinguishing spectral lines, does this mean the space dust table is needed for that too?

I seem to recall someone describing molecular hydrogen bonding from some associative electron spin characteristic, wherein the timing of charges between the electron swings and their respective protons bring about the union. But then, too, I forget a thing or two from time to time.

[Gabe]

so whats the dusts molecular composition?

[dave_f]

Originally posted by Gabe@Jun 23 2005, 06:53 PM
so whats the dusts molecular composition?

Here's my guess:

This question can be answered by the statement "It doesn't matter". Dust tends to be made of inert matter (i.e. matter not prone to chemical reactions), beacause if they were chemically reactive, they would have undergone those reactions already. Dust tends to stick around for a loooooong time. This is especially true for the interstellar variety.

The experiment only involved looking at surfaces, not the chemical reactions of those surfaces. Additional chemical reactiveness of the surfaces themselves would be largely inconsequential, since the sheer number of hydrogen atoms far outnumber the amount of dust particles. The hydrogen wins, hands down.

[lswinford]

Here's an excerpt of something I stumbled onto recently, it may help:

I recently read an article by Katharina Lodders and Sachiko Amari ("Presolare grains from meteorites: Remnants from the early times of the solar system"), Geochemistry, vol. 65, issue 2 (May 23, 2005). They described how what is essentially star dust, the solid and mineral matter from ancient stars going nova or otherwise ejecting matter into the interstellar medium. In their situation, the search was for "presolar grains" or such solid particles in meteorites on earth, which they think they've found several examples, especially in stoney, or carbonaeceous chondrites....They discussed uranium and plutonium fission residues, titanium, nickel, sodium, silicon, iron, carbon (lots of carbon, often with nanoscale diamonds), oxygen, aluminum, and more.

[blueshift]

These are all interesting points. I am a bit curious about a few other things here.
While my background in molecular science is quite limited, I do recall that molecule structure and behavior is interdependent with shape.

If you scoll down to the April 25 blog right HERE, you will get a good primer from a SLAC scientist how plasma can form wakefields and produce accleration of electron bunches in the research her team is doing.

Could this also have occured in the early molecular dust cloud of our solar system before the Sun's birth?

Worldlines in the middle of the cloud would have been producing more collisions than the the outer extremeties would have..Smoother surfaces would have resulted there, liberating large amounts of molecular hydrogen. This lighter gas would have been more easily accelerated by the wakefield effect than heavier substances would have.

I would think that more and more hydrogen would have then concentrated near the molecular cloud center with higher speeds and greater and greater densities forming since more and more wakefield effects would exist there. Temperature would rise.

Yet not all world lines remain on collision courses. Smaller, smoother dust grains would have been accelerated into collisions, forming into shapes that would take back some of the earlier liberated hydrogen. Some of those would have followed a non colliding journey, reaching the outer edges of the dust cloud and forming into the makings of comets. Eventually larger molecules like cyanogen could adhere to the particular shape and surface features of what we see today.

I think we should get the answer to this hypothesis within days. If Deep Impact lilberates some trapped hydrogen gases and then the new trajectories of debris attract different types of molecular gases, this could hold water..(in the figurative and literal sense).

Odds are against it...My emotions prefer a surprise to my hypothetical expectations..I am sure that someone here can poke a good hole into this and reveal its errors.

[dragonmaster_us@hotmail.com]

I think that the question of how the dust became 'bumpy' is going to reveal some interesting details to the Early Universe models. Coming from a mechanical viewpoint, the obvious conclusion would be that there were impacts on the particles by smaller than atomic sized projectiles. That points to a highly energetic environment where photonic wearing could take place. After 14 Billion years, I'm surprized that a dust particle would still be around for us to theorize on, rather it would have been smashed apart into it's own constituent atomic particles. My experience and training has shown that atoms can be inticed into a molecular form by a roughened surface, as long as the surface features are small enough. On a smooth surface, the same efforts fail, or form crystaline lattices that continue to grow. Sputtering ovens take advantage of the effect in producing IC chips on smooth surfaces, and, our bodies take advantage of the molecular fit to uneven surface features for everything from immunology to procreation and cellular regeneration. It is no surprize that nature also uses the process to increase the complexity in the environment of the interstellar/galactic medium. I refer to many of my statements here and in other places that natural processes will lead to more complexity in any environment that is not explicitly hostile to complexity (ie. inside a black hole.)

[biknewb]

Originally posted by Gabe@Jun 24 2005, 01:53 AM
so whats the dusts molecular composition?

And what is more puzzling: when there was nothing but hydrogen atoms in a very early universe, where did the (molecules of the) dust come from?

[antoniseb]

Originally posted by biknewb@Jul 25 2005, 01:14 PM
when there was nothing but hydrogen atoms in a very early universe, where did the (molecules of the) dust come from?

When there was nothing but cooling Hydrogen ions in the early universe (and some Helium and a little bit of Lithium) there was no dust. There was also no (or very little) ionizing radiation to keep the ions excited. So the universe cooled off, and electrons teamed up with protons and formed atoms, without the need for protective dust to accelerate the process.