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Author Topic: What causes the formation of globular clusters?  (Read 1722 times)

Offline Geezer

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What causes the formation of globular clusters?
« on: 09/02/2010 21:33:29 »
Come to that, why does anything congregate in space?


 

Offline Vern

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What causes the formation of globular clusters?
« Reply #1 on: 09/02/2010 21:54:45 »
I don't know of anything better than gravity.
 

Offline Soul Surfer

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What causes the formation of globular clusters?
« Reply #2 on: 10/02/2010 20:59:23 »
Universal gravitation is the only reason why planets, stars, galaxies and clusters of galaxies form in the first place but as the cosmic microwave background (CMB) shows clearly the early stages of our universe were amazingly smooth and uniform. within a mass of uniform material of indefinite extent  (see topic  http://www.thenakedscientists.com/forum/index.php?topic=28664.0 )  there is no net gravitational field in any direction.  This is why astronomers are so keen on measuring the very slight deviations from uniformity of the CMB.

The next thing to think about is the way gravitational collapse takes place. Things tend to collapse from the inside because small objects tend to have shorter relaxation times than larger ones.

Collapse occurs until stars form,   The very first stars were probably very different from today's stars because initially there were no intermediate elements  ( C N O ) to help catalyse the nuclear synthesis process so they had to be much bigger before they could produce significant amounts of energy it is also possible that some of the very biggest concentrations collapsed directly into black holes to form the quasars a feature of our early universe that is rare now.

After that it was generally assumed that galaxies and clusters of galaxies just formed but the mechanisms were not fully described.

Just recently it is starting to be considered in more detail how these first stars affected the structure of our universe.  it was first realised that they would be responsible for the re-ionisation of the gas and the introduction of tiny quantities of carbon nitrogen and oxygen and heavier nuclei into the gas that enabled more normal stars to form but the affect of the radiation from and the explosions of these first supernovae was not looked at seriously in its effects on the structure.
« Last Edit: 10/02/2010 22:54:06 by Soul Surfer »
 

Offline Soul Surfer

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What causes the formation of globular clusters?
« Reply #3 on: 10/02/2010 20:59:46 »
Recent papers suggest that the jets from quasars could form spiral galaxies quickly by compressing the gas already falling towards the quasar into a disc

I also think that these early supernovae could form globular clusters by compressing the infalling gas with their spherical shock waves.
« Last Edit: 10/02/2010 22:57:32 by Soul Surfer »
 

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What causes the formation of globular clusters?
« Reply #3 on: 10/02/2010 20:59:46 »

 

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