Our solar system's hydrogen -- from where??

[EWyatt]

The gold in my molars, the uranium within the earth, and all the other heavy elements in our solar system were once "created" by our local "mother" star that had gone supernova -- you know the drill. Its demise was caused by lack of fuel (hydrogen, helium ....iron) to burn, so it went boom, and all resultant local matter was spread around thinly in a nebula (I'm assuming). So now, after a few billion years, here comes our newly-ignited Sun and solar system, rich with hydrogen, and helium! So where did this "new" hydrogen come from? The supernova blasted away any hope of remaining hydrogen. Did gravity from the resultant nebula just suck in more hydrogen from a few light years around our system? Or what? Or did God just create "new hydrogen" for us just to show us he's our bud?

 

Thanks....

Edited March 9, 2012 by EWyatt

[Schrödinger's hat]

The gold in my molars, the uranium within the earth, and all the other heavy elements in our solar system were once "created" by our local "mother" star that had gone supernova -- you know the drill. Its demise was caused by lack of fuel (hydrogen, helium ....iron) to burn, so it went boom, and all resultant local matter was spread around thinly in a nebula (I'm assuming). So now, after a few billion years, here comes our newly-ignited Sun and solar system, rich with hydrogen, and helium! So where did this "new" hydrogen come from? The supernova blasted away any hope of remaining hydrogen. Did gravity from the resultant nebula just suck in more hydrogen from a few light years around our system? Or what? Or did God just create "new hydrogen" for us just to show us he's our bud?

 

Thanks....

 

Stars don't burn all of the available hydrogen before they die. They just burn up enough that they can't burn what remains at a rate fast enough to stop the star from collapsing which could have merged with the expanding debris.

There would have also been other gas clouds that had not collapsed.

Edited March 9, 2012 by Schrödinger's hat

[EWyatt]

Stars don't burn all of the available hydrogen before they die. They just burn up enough that they can't burn what remains at a rate fast enough to stop the star from collapsing which could have merged with the expanding debris.

There would have also been other gas clouds that had not collapsed.

 

Ummmm.... so after the supernova, you're saying there was enough hydrogen left for a new solar system w/ sun? Really?

[D H]

Really. Supernovae are characterized as Type I or Type II, depending on whether the supernova has hydrogen lines in its signature. Another source for the hydrogen is mass loss in the form of solar winds experienced by a star well before it went supernova. Even our Sun, which is too small to form a supernova, loses some of its mass to the solar wind. We just had a near miss earlier this week from a coronal mass ejection. Massive stars undergo much more extreme mass loss. The most massive stars eject a good chunk of their original mass between their original formation and their deaths as supernovae.

 

However, most of the Sun's hydrogen probably never formed into a star in the first place. Star formation is rather inefficient process. The vast majority of the gas cloud from which a star forms doesn't get drawn into the star. Some of the gas does collapse, but only in the protoplanetary disk. Those gas giants are just as inefficient as are stars with regard to gobbling up mass. The stuff in the disk that doesn't form into planets gets blown away when the star ignites. Only 10% or so of the original gas cloud forms stars. The other 90% gets left behind and dispersed.

[Schrödinger's hat]

DH,

Is it more that the supernova ejects mass into surrounding/remaining clouds, or that clouds condense more rapidly on the supernova remnant?

[MigL]

The primordial fast-burning star which gave rise to 'our' heavy elements was formed at a time when hydrogen clouds were more abundant and vast than they are today, much like the difference between outer spiral arms and central regions.

I believe it is the nova/supernova shock wave which causes the compression waves in surrounding interstellar gas clouds, and is the cause of the initial 'seeding' of new stars, before gravity completes the task.

[Schrödinger's hat]

The primordial fast-burning star which gave rise to 'our' heavy elements was formed at a time when hydrogen clouds were more abundant and vast than they are today, much like the difference between outer spiral arms and central regions.

I believe it is the nova/supernova shock wave which causes the compression waves in surrounding interstellar gas clouds, and is the cause of the initial 'seeding' of new stars, before gravity completes the task.

 

So I understood, but I've never seen it mentioned in any of my astro texts as to whether the hydrogen travels to the heavy elements or the heavy elements travel to the hydrogen.

It seems likely that it's the latter if I apply my brain, but physics isn't always what seems obvious.

[D H]

The primordial fast-burning star which gave rise to 'our' heavy elements was formed at a time when hydrogen clouds were more abundant and vast than they are today, much like the difference between outer spiral arms and central regions.

Only a small percentage of the hydrogen that was present shortly after the big bang has been fused into more massive elements. About 75% of the ordinary matter was hydrogen just after the big bang. Today, that figure has dropped by a tiny bit, to 73 to 74% or so. The vast majority of the primordial hydrogen is still hydrogen today. The universe will undergo a "peak hydrogen" problem eventually, but that problem is a long, long way into the future.

 

While there is some recycling of hydrogen in stars, most of the hydrogen in our Sun was never captured in a star before it was captured by our Sun. Star formation is quite inefficient. Most of the hydrogen in the parent gas cloud doesn't collapse into the protostar. A good chunk of what does collapse is ejected when or shortly after the protostar ignites. In massive stars, there is extensive mass loss throughout the star's life. There might be very little hydrogen left by the time the star goes supernova. Whether there is or isn't any hydrogen left in the star at the time it goes supernova is what distinguishes Type Ib/Ic supernovae from Type II supernovae.

 

While some of our Sun's hydrogen may have been a part of a star at the time it became a Type II supernova (those where some hydrogen is left), most of our Sun's hydrogen did not come from a supernova. It was just out there in the interstellar medium all along.

Edited March 10, 2012 by D H

[EWyatt]

Thanks to all, esp DH, for the excellent responses.

[Airbrush]

Interesting discussion. So I was also thinking that could a nearby supernova "push" hydrogen of the interstellar regions into the area where our solar system formed, and our solar system formed from a mixture of heavy elements from the supernova plus hydrogen that was either blasted off or that was pushed into our area?