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Peter,
Very Sad to hear about the passing of your friend, but your new supernova is bringing life to the universe by creating and ejecting many of the chemical elements that are necessary for life to exist. All that existed originally in the universe was a whole lot of hydrogen and helium, and perhaps a little bit of Lithium; there was nothing exciting in this universe 14 billion years ago, not even stars and galaxies.
In this universe of ours, there is always creation, and always destruction, and always both life and death, so it is natural to wonder what it all means when someone that we like passes away prematurely.......
Think of the entire planets that can be destroyed by a supernova, but then think of how a colossal supernova explosion seeds the interstellar medium with more of the precious substances such as the carbon and nitrogen which are essential for organic lifeforms to exist......
Burbidge, Burbidge, Fowler, and Hoyle quoted (from King Lear) at the beginning of their famous 1957 paper about the synthesis of heavy elements within stars:
"It is the Stars, The stars above us, govern our conditions".
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I have just happened to be writing about the chemical enrichment of the cosmos in a recent article that I am working on. Here is a quotation from part of my draft article: (note that this may not yet be 100% accurate as it has not yet been reviewed)
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quotation from madbadgalaxyman's article on stellar populations and chemical enrichment.......
Stellar Generations - episodes of star formation alternating with chemical enrichment of the ISM
When a single generation of stars forms, normally in a short period of time relative to the full lifetimes of the stars that have formed, it is usually produced from interstellar gas which has been enriched with heavy elements originating in the nuclear reactions that took place in previous generations of stars. The previously formed generation(s) of stars eject gaseous material (and also tiny granules of solid materials) , into the surrounding interstellar gas, and some of this gas will then become the raw material that is incorporated into new stars when future generations of stars form from the interstellar gas. The previous generations of stars have produced heavy elements by means of nuclear fusion reactions in their cores, and some of these stars then eject this 'heavy element enriched' gas into the surrounding interstellar medium by means of various types of gas outflows:
- stellar winds (gas outflows) from distended giant and supergiant stars
- the gas that is expelled as a planetary nebula
- gas ejection from supernovae, mainly of Type II and Type Ia .
Here are some important examples of how previous generations of stars can create heavy-element enrichment of the Interstellar Medium (ISM) and the stars that form from the ISM :
(1) Heavy element enrichment in the Sun ; The composition of the gases in our Sun has the following approximate mass fractions: X=0.70, Y=0.28, & Z = 0.02. By convention, X is the fractional abundance of hydrogen in a star (or in a region of the ISM), Y is the fractional abundance of helium in a star (or in a region of the ISM), and Z is the abundance of all elements heavier than hydrogen and helium. (Astronomers quaintly refer to all elements heavier than hydrogen and helium as 'metals' ! ). This elemental composition of our Sun differs significantly from the mass fractions in the primordial gas from which the very first generations of stars formed; the mass fractions in the primordial gas are approximately X = 0.76 and Y = 0.24 and Z = 0.00 .( remember, X = mass of hydrogen divided by the total mass of gas, Z = the mass of metals divided by the total mass of gas, and Y is the same for helium. Therefore X+Y+Z = 1 ).
Thus if Z equals 0 before any stars formed in the universe , there were no heavy elements ('metals') in existence in the universe at that time, before the first ever generation of stars came into being. So all of the metals (I will adopt this common usage from now on!) in stars and the ISM had to be produced later on by nuclear reactions within stars and the ejection of some of these fusion products when the stars reached the ends of their lives. Thus, that small fraction of 'metals' found in our Sun and Solar System had to be produced by previous generations of stars! Note also that the primordial helium abundance of Y=0.24 is considerably less than the helium abundance of Y=0.28 that is observed in the Sun; this additional helium in the Sun originated inside previous (now dead) stars, in which helium was produced by fusing together hydrogen atoms.
(2) Alpha element enrichment ; alpha elements in the interstellar gas are mainly produced in Type II supernovae. The alpha elements (also known as the alpha-particle elements) are those which are built up within stars using alpha-particle nuclei, and they include C, O, Ne, Mg, Si, S, Ar, & Ca (Carbon, Oxygen, Neon, Magnesium, Silicon, Sulfur, Argon, Calcium).
(3) Iron enrichment ; iron (chemical symbol Fe) & Cr in the Interstellar Medium are mainly produced by supernovae of Type Ia . The interstellar gas is enriched with iron-group elements like Fe & Cr by Type Ia supernovae. The synthesis of iron is thought to result from extremely rapid nuclear fusion reactions in a Type Ia supernova; carbon is 'ignited' in a white dwarf that has accreted enough material from a companion to to push it over the Chandrasekhar mass limit.
Type II supernovae are produced by massive (>8 solar mass) stars at the ends of their short lives, while Type Ia supernovae are produced by the long-term evolution of, and accretion by, a white dwarf star. Hence, the Alpha-element/ Fe abundance ratio in the ISM (and in the stars that form from the ISM) depends on the relative contributions of these two types of supernova; because Type II events occur rather quickly after the formation of the progenitor star of the supernova, and Type Ia events occur after a much longer elapsed time, the alpha-element/Fe ratio is diagnostic of the time scale over which star formation has occurred (Thomas et al., 2005, ApJ, 621, 673).
End of quotation from madbadgalaxyman's article
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