Mystery of missing hydrogen
November 24th, 2008Something vital is missing in the far distant reaches of the Universe: hydrogen - the raw material for stars, planets and possible life.
The discovery of its apparent absence from distant galaxies by a team of Australian astronomers is puzzling because hydrogen gas is the most common constituent of normal matter in the Universe.
If anything, hydrogen was expected to be more abundant so early in the life of the Universe because it had not yet been consumed by the formation of all the stars and galaxies we know today.
Dr Steve Curran and colleagues at the University of New South Wales made their observations with the Giant Metrewave Radio Telescope in India, which comprises thirty 45-metre-diameter dishes and is one of the world's most sensitive radio telescopes. The results are to be published in a forthcoming issue of Monthly Notices of the Royal Astronomical Society.
By looking at galaxies in which the light has taken over 11.5 billion years to reach us, they found an apparent lack of hydrogen when the Universe was only two billion years old - long before our own Sun and all other stars in the present Universe had formed.
Stars form when extremely cold clouds of hydrogen collapse under their own gravity until they become dense enough to ignite nuclear fusion. Over billions of years, this leads the formation of the heavier elements that make up planets, people and other matter. Each galaxy should contain gas masses equivalent to several billion stars, as in the Milky Way.
"Since hydrogen gas is consumed by star formation, we may expect more hydrogen gas in the distant, and therefore earlier, Universe as all of the stars we see today have yet to form," Dr Curran says.
His group analysed the data from optical telescopes and found that, although apparently dim due to their immense distances, the distant galaxies actually emit vast amounts of energy.
This energy is generally believed to result from the friction of the material spiralling at close to the speed of light into the black hole lurking within the heart of each galaxy. These "quasars" are found all over the sky but occur predominantly in the early Universe.
"At such distances, only the most optically bright objects are known," Dr Curran says. "The intense radiation from the matter accreting into the black hole in these quasars is extreme and we believe that this radiation is ripping the electrons from the atoms, destroying the hydrogen gas."
This would leave the gas as a soup of free subatomic particles known as a "plasma", which cannot be detected at the radio frequencies searched.
"Searching for neutral hydrogen in quasar host galaxies at such distances is really pushing current radio telescopes to their limits," Dr Curran says. "With the next generation of instruments, such as the Australian Square Kilometre Array Pathfinder, we may be able to probe deep enough to find just how ionised the gas is.
"Meanwhile, astronomers should search for sources of radio emission that have no optical counterpart. The emission tells us that something invisible to an optical telescope is there. Such galaxies would host more benign quasars in which we may detect the neutral gas."
Source: University of New South Wales
Jun 24, 2009 |
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"Stars form when extremely cold clouds of hydrogen collapse under their own gravity until they become dense enough to ignite nuclear fusion."
You can look me in the eye with a straight face and tells me this makes perfect sense? Let me get this straight... A massive cloud of "gas" spontaneously freezes into a large ball, continuing to increase in mass by its own self defining force until it gets so "heavy" in a near vacuum low pressure environment that it then spontaneously goes from a few degrees above absolute zero to become a blazing inferno in which the self attracting mass begins to fuse into denser masses and continues to hold itself together while it is virtually tearing itself apart.
I suppose this is almost plausible if you suggest that the "gas" cloud is rotating at a high velocity creating a low pressure epicenter to begin the above described process.
And I'm not going to get into it, but yes, par for the course, there isn't even a hint of electromagnetic forces at work, granted this is not the focus of the article.
Just as the side-view mirror say 'Things are closer than they appear'
I believe in these cases, things are definitely not as they seem, and imo, they really need to drop the observation of long range objects.
Firstly, You need to understand the terms at play. Gas means not a liquid, not a solid, not a plasma. Cold due to the lack of excess energy beyond it's base state. There is no weather like pressure system in space. Rotation does not cause a vacuum to form. Space itself is the vacuum.
When enough of the particles come in contact a few will stick together, making them more massive and in turn more apt to attract more gas.
As the gas condenses, (yes, becomes a liquid, or in this case plasmoid) the mass and gravitation increase greatly. Eventually the gravitation increases so greatly that between friction, and other forces, fusion begins.
http://www.presto...ndex.htm
As the particles race inward toward each other, they shed Gravitational Potential Energe (GPE) and gain kinetic energy. This energy is what helps kick off fusion at the core of the collapsing GMC.
But the amount of energy required to trigger fusion is lower than classically expected due to quantum tunneling.
So, earls, the cloud doesn't need to have a center, just density irregularities that will eventually start the collapse process.
Better would be to say we have hydrogen floating in space. It is considered cold because if it has more energy and moves faster that is considered hot and will not clump.
The cold hydrogen has gravity but it is not very strong. When you have a large amount of hydrogen the gravity is added together.
Again if it was hot it would scatter but if it is cold it will not scatter. Since it is cold it can pack a little closer together and thus acquire more gravity.
As gravity increases it is easier and easier for the hydrogen and other matter to get closer together. Eventually we have a solid ball of matter of whatever size depending on the quantity of hydrogen and other matter floating about.
This ball of matter will suck in via gravity all the hydrogen and other elements in the vicinity. If there is enough it will form a big enough ball of matter that will create great heat in the center because of the compression forces due to gravity.
If the compression forces gets great enough to overcome the heating effect due to gravity compression then you will get fusion which gives off more heat as a byproduct.
Again the actual size of the original cloud of matter is very important if it is not very big you end up with a planet size lump. bigger and it could burn out in a minutes or days. Much bigger and you get a sun.
I think that is a better explanation.
Quite simply put, mass attracts mass, via the gravitational force.
Given a finite amount of mass, there must be a center of mass; and, if the matter is not uniformly distributed, there may also be local centers of mass.
Every particle having mass will be attracted to a center of mass, regardless of its thermal energy; in so doing it will accelerate, thereby gaining kinetic energy.
When enough matter with enough kinetic energy has collided, nuclear fusion is initiated.
Temperature is a measure of average kinetic energy of particle motions therefore as the particles accelerate in the gravity field their temperature increases.
Gas exchanges its gravitational potential energy to kinetic energy.
As it collapses it also lowers its volume which leads to rise in pressure (which depends on average number of particles in a volume and their temperature).
This rise in temperature and pressure will counteract the gravitational collapse to some extent but as the gas heats up it also starts radiating energy away in addition some molecules escape carreing excess kinetic energy with them which also serves to cool the matter.
This cooling allows collapsing to continue further until at some point the temperature in the center reaches extreme enough values to ignite nuclear reactions which then provide the outward pressure and the star reaches equilibrium.
The gravity pulls matter inward while the radiation and heat from nuclear reactions pushes it outward.
Electromagnetic effects do of course play a role, the pressure is due to electromagnetic forces, as is the radiation which cools the cloud. The collapsing gas gets ionized at some point creating plasma currents and immense electromagnetic fields which further stir the matter.
Here we are, with a multi-billion station in space, and all we're trying to do is drink our own pee ! (?) Ghandi did it without a million-dollar machine, and lived to talk about it.
This is an invaluable opportunity, and so much has been sacrificed, when will we finally use it to actually advance mankind???
The GE Fusion pattern plant is our solar reaction playground.
Does the disprove the Big Bang by any chance??
We have simple models that are good for the computer power of the moment and that get better with time and account for more and more types of interactions. Then you hit "enter" and watch.
(sorry if I offend someone, but I prefer pictures than words-no matter how logical something sounds, until it's modelled and checked for consistency with the real data, it's just a speculation)