cats eye

[Empeda]

Yes I think that;s the problem - I like the way Dave thinks, it's refreshing and I love the ideas, but too often he is stating them as fact.

[davecorsby]

I seem to be aware of more opinions than you are.

How, when, and where were the elements of the Earth formed?
When did they become part of our solar system?
Where is the proof that asteroids and comets formed in the solar system, and not outside it?
What was the nature and contents of the cloud our solar system coalesced from?
How many novas and super novas contributed to it?

When the KT boundary was established, scientists “learned” all meteoroids contain lots of iridium. They also “know” meteoroids don’t contain any copper. I think that is ridiculus!
Take a look at other impact created boundaries and you will find the mineralogy is vastly different in each case. Why so much diversity?

I'd love to hear the Facts as you see them.

[orin stepanek]

here is one place to look. This site sugests that tth heavy elements were created in super nova.
Orin

[orin stepanek]

Just wanted to show where these larger element may be formed. Doesn't light spectrum show what a stars composition may be?
Orin

[Empeda]

Yep - that's how Helium was discover by analysing the sun - it's name come from Helios....

Heavier elements are formed in stars, but not like dave was desribing. A very simplistic example is:

Hydrogen -> Helium
Helium -> Carbon, Nitrogen, Oxygen

Note that Lithium, Byrillium etc are skipped - Lithium cannot be created by fusion, only fission - which is why astronomers are quite intrigued by how much there is in the universe.

[S. Bilderback]

Just wanted to show where these larger element may be formed. Doesn't light spectrum show what a stars composition may be?
Orin

The core of most stars are plasma and nearly all the rest is H and He and contain a very small % of the heavy elements, or at least not until some of their last dieing breaths. The heavy elements above Fe are formed during super nova explosions; the heavy elements require a large amount of energy to create by fission and not fusion. The heaviest element are formed in the super heated gasses as the nova's shock-wave of supper heated protons and neutrons collide with the nebula dust containing the heavier elements forcing the creation of some of the heaviest elements where they hang out until a new star forms.

Here's a cool site for more information.
http://imagine.gsfc.nasa.gov/docs/ask_a ... 1112a.html

[craterchains]

Uhhhhmmm just a thought based on that info, how then do we get heavy elements on earth at the depths and on the surface as we do?

Norval

[S. Bilderback]

The heavy elements are mixed throughout the planetary nebula, as a solar system forms, the star ignites and the proto planets form. Most of the heavy elements in the proto star are heated and crushed by the proto star's gravity becoming part of the plasma at the core. As the planets form, the lighter elements are push farther out by the solar winds, the average density of the planets in our solar system decrease the distance from the sun increases. The formation of our planets was a very violent start keeping the elements well mixed. The average density of the Earth also decreases in relationship to the distance from the core. The core is mostly Fe and Ni, the surface is mostly Si compounds.

[mgeorge]

Has any attempt been made to estimated rate of production of the heavier elements and compare that to the known quantities of these present? Eg. how long and how many stars would it take to make the iron and nickel present in the earth's core? How does that compare to the "known" age of the universe?