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What's the third most common element?

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Re: What's the third most common element?

#21

What caught my eye was the oscillation in the abundancy graph, there is a tendency for even atomic number elements to be more abundant than odd atomic number elements. Looking at the original Wikipedia article leads to the Oddo-Harkins rule http://en.wikipedia.org/wiki/Oddo%E2%80%93Harkins_rule . There is more discussion on the stability of even vs odd atomic number elements here: http://en.wikipedia.org/wiki/Even_an…

How odd..

Re: What's the third most common element?

#22
post #18

Earlier quoted context omitted.

Still can't conclude it from just the data presented here.

You have to explain more than that

You provided a conjecture based on incomplete data as fact, he stated that it's conjecture until additional data to support it is there... the burden in this situation is not on him.

Re: What's the third most common element?

#26

I've always wondered how elements produced in past stars end up in our solar system. I wouldn't think the whole universe is getting remixed all the time. It seems like areas stay pretty isolated.

At the universal scale, we can observer several galaxies in various stages of colliding with each other (1). In fact our galaxy and Andromeda are on course to collide with each other in about 4 billion years (2).

Massive stars end their lifecycle in a supernova explosion, which blasts much of their mass off into space. the remaining stellar core either forms a neutron star or a black hole. The mass that is blated off contains many heavy elements formed in the star by nuclear fusion, and contributes to nebula formation. These nebulas coalesce to form new stars and their associated planetary systems. We can actualy see this happening in various places throughout our galaxy, with nebulas in various stages of coalescing and with multiple stars forming within them. Absorbtion spectra tell us about the materials these nebulae are composed of.

There is some speculation that heavy elements such as iron are also produced and scattered about in nutron star collisions.

(1) http://en.wikipedia.org/wiki/Galaxy_collision (2) http://en.wikipedia.org/wiki/Andromeda_galaxy#Future_collisi...

Re: What's the third most common element?

#27
post #13

Earlier quoted context omitted.

No we can't. If it's not molecules, it's not water, and there's nothing here to indicate whether the hydrogen and oxygen are found bound together.

https://en.wikipedia.org/wiki/Water#In_the_universe While water will break down at high temperatures I would find it surprising that 1st and 3rd most common elements in the whole universe, that readily combine to form water would not result in substantial amounts of water. It's probably like saying we shouldn't find H2 because "nothing says they are found bound together"

Most atoms- and certainly most hydrogen- are in stars, no? Not exactly places where water "breaking down at high temperatures" (really, never forming) can be ignored.

Re: What's the third most common element?

#28

Is big bang necessary for this or does any amount of photons of insanely high energy crystallize in matter in those proportions?

As I understand it, something like the big bang produces mostly light elements -- hydrogen and helium. Everything else is produced in the stellar fusion machine plus supernovas.

So, by the time that the heavier elements are forming, the big bang has been done with and forgotten about for at least, like a microsecond. ;-)

Re: What's the third most common element?

#29
post #22

Earlier quoted context omitted.

You have to explain more than that

You provided a conjecture based on incomplete data as fact, he stated that it's conjecture until additional data to support it is there... the burden in this situation is not on him.

> You provided a conjecture based on incomplete data as fact,

No, I never said it is a fact, it is, as you pointed, a conjecture, and I provided a source (ok, wikipedia) for the amount of water in the universe

If you or him knows of a reason for why the most common elements in the universe that combine easily wouldn't result in an abundance of their combination I'm all ears.

(Which doesn't mean the amount of water is going to be near the amount of H2 or just the amount of Hydrogen present in the stars)

Re: What's the third most common element?

#30
post #26

I've always wondered how elements produced in past stars end up in our solar system. I wouldn't think the whole universe is getting remixed all the time. It seems like areas stay pretty isolated.

At the universal scale, we can observer several galaxies in various stages of colliding with each other (1). In fact our galaxy and Andromeda are on course to collide with each other in about 4 billion years (2). Massive stars end their lifecycle in a supernova explosion, which blasts much of their mass off into space. the remaining stellar core either forms a neutron star or a black hole. The mass that is blated off…

Interesting. So where did our sun come from? Are you saying it started from a multilight year wide cloud?

Why is it 4+ light years from any other stars? Did our sun pull everything out of that radius when it was forming leaving a whole bunch of empty interstellar space?

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