Astrophysics


Tracing the origin of the various chemical elements is still an active area of research. This overview represents a view based on the most recent data. Ten types of forge processes are mentioned here. Many elements seem to have been formed by at least two different processes. It is to be expected that in the coming years sophisticated observations made by the James Webb Telescope, among other telescopes, will enable us to refine this overview.

Important forging role for novae
The numbers for lithium are still highly speculative. To map the cosmic origin of lithium is an active area of research. The latest astronomical data seem to suggets that lithium mainly has been formed during novae.
A nova is a transient periodical event during which an accretion disk of hydrogen around a white dwarf is nuclear ingited causing an explosive runaway fusion process.
This hydrogen in the accretion disk is acquired from an orbiting companion star.

Current spectroscopic observations on novae also seems to indicate that during the nuclear fusion processes besides Li also He, C, N, O and Ne are produced. In the table above behind those elements in column 5 an "x" is representing the figures which still have to be estimated.

Our Sun is at least a third generation star
Spectropic analysis of various stars and remnants of stars has learned us a lot about the origin of elements.
Our solar system including our Sun contains a lot of heavy elements. It means that our Solar systems must have been formed out of remnants of ancestor stars.

We know that some elements are forged inside a star out of elements which must already have been there since the birth of that same star. 56Ba is such an example. This element is made out of other elements (see table, forge process 7). Spectroscopic analysis has revealed that our Sun contains Ba which cannot be formed by the Sun herself. It must have been made by her predecessor at earliest. If that is the case, than this predecessor must have contain other heavy elements, which in turn have been made by her predecessor at earliest, from which Ba can be formed.

So our Sun is at least a third generation star. But it is likely that the origin of our Sun is more complicated. Some five billion years ago (when our Universe was about eight billion old) she might have been formed out of remnants of multiple stars each with their own history of ancestors.


This plot gives a resasonable good impression of the average relative abundances of the chemical elements in our galaxy.
The plot is based on spectroscopic measurmenents of the Sun, stars and the interstellar medium. Also analysis of cosmic rays, which contain atomic nuclei, and chemical analysis of samples of meteorites and astroids provides information about the abundance of chemical elements.
It is to be expected that this plot might somewhat differ between the various locations in our galaxy.

To produce such a plot for other galaxies is an active area of research.
Who knows whether such plots might provide a unique galactic fingerprint because of the unique evolution and age of each galaxy.

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