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stitt29
2009-Apr-12, 12:22 AM
Does anyone know how solar nebula are formed. I am thinking of nebula like the eagle nebula. As far as I can gather these are clouds are full of gas and dust that, in theory, go on to accumulate into stars. How do these massive clouds come about in the first place?

Moose
2009-Apr-12, 10:41 AM
You might find the wikipedia article on the Nebula (http://en.wikipedia.org/wiki/Nebula) helpful. There's a decent section on nebula formation.

stitt29
2009-Apr-12, 12:44 PM
So if solar nebula are formed from a supernova. e.g. the crab nebula is a supernova remnant; How was the star that became the supernova formed? Also a supernova remnant would only have enough mass to collapse into a new Star which would have less mass than the original. So are all newer stars smaller than their predecessors? How many generations of stars have there been in the last 14billion years and how were the original nebula formed?

antoniseb
2009-Apr-12, 01:13 PM
The supernovae's shock waves act like a snow plow piling up loose snow (gas and dust) that was previously more sparse, but gets piled up in thick piles along the side of the road. The SN themselves do not have enough mass to create the star forming regions simply with their own ejected mass.

Wizard From Oz
2009-Apr-12, 01:58 PM
So if solar nebula are formed from a supernova. e.g. the crab nebula is a supernova remnant; How was the star that became the supernova formed? Also a supernova remnant would only have enough mass to collapse into a new Star which would have less mass than the original. So are all newer stars smaller than their predecessors? How many generations of stars have there been in the last 14billion years and how were the original nebula formed?

Defining the number of generation of stars is difficult because different stars burn at different rates. Example stars as massive as Eta Carinae have a life span of only a few million years. Star such as Proxima Centauri could be looking at a life span measured in trillions of years.

There is an upper limit to the actual size a star can get too. So these stars wont continue to draw in gas forever. Once these early stars formed, the remaining gas floated around waiting for something interesting to happen.

These stars supernova, add their debris to the rmaining clouds and the process begins again

It also needs to be remembered that galaxies are not static. They are constantly merging, drawing in new stars and gas into their system from passing smaller galaxies and such.

rommel543
2009-Apr-14, 07:18 PM
Could not a star the size of Eta Carine eject enough material over time that would cause the creation of a smaller star such as a red dwarf?

aurora
2009-Apr-14, 08:38 PM
There are other kinds of shock waves that can create star forming regions, for example due to the interaction of galaxies that pass close to each other.