Where Atoms Come From: "We Are All Star Stuff"

     Over the years, there have been many theories about where elements come from. Some said elements "just are." Others relied on the big bang theory. Goeffrey Burbidge, Maragret Burbidge, William Fowler, and Fred Hoyle all worked to "explain the theory of stellar nucleosynthesis in a famous 1957 paper" known as B2FH. This whole paper accounts for the elements up to iron, the "final peal of a star's natural life" in one explanation of stars and how they function.Then it says the elements from cobalt to uranium were created, or emerged, from mini versions of the big-bang. A supernova also creates new elements, after it explodes and neutron-coated iron nuclei decay back into protons.
    Many stars have gone through this process in other galaxies and even in our own. It is believed that one of these explosions created our solar system. Planets formed when dust particles and the spume from the supernova started to mix and swirl in pools. "The dense center of the cloud boiled up into the sun" and planetary bodies developed. Most of these planets have fascinating histories. Some were used to name elements, even if those elements do not make up a significant part of the planet. There are hopes that some planets have diamonds larger than the earth in a solid state. On a planet such as Jupiter, the largest planet, many elements exist in rare forms that aren't seen on earth. This is due to the extreme conditions on Jupiter. The rocky planets formed after the gas giants (planets like Jupiter), and they are a blend of many elements. As for the earth, Clair Patterson was the one who came up with the best estimate of how old the earth is: 4.55 billion years. He did this by analyzing the amount of lead in the Earth and using a lot of different information. (He is also the reason that society knows things such as lead paint and leaded gas are dangerous!)
     When Luis and Walter Alvarez were studying limestone deposits, they discovered a lot of iridium, which is rich in meteors, asteroids, and comets. This eventually led to the theory of how dinosaurs became extinct. However, dinosaurs were not the only species that went extinct. Thin layers of iridium-rich clay coincided geologically with many other extinctions. This new information supported the Alcarez's theory even more. Then, another element, rhenium, started a whole controversy on a companion star that supposedly flings rocks and asteroids at the earth periodically. This is what some scientists, such as Alvarez's colleague Richard Muller, believed explained the extinctions that occurred billions of years ago. This star, which was named Nemesis, has yet to make an appearance to scientists. For this reason, this theory is questionable.

     Basically, the sum of this chapter was, as Carl Sagan put it, "we are all star stuff." Stars were the beginning of our world, and they most likely will be the end of it, too.