What does “We are children of the stars” literally mean?

The phrase “star children” has now entered our common language. Let's break down what this actually means

Models that explain, starting from simple physical and thermodynamic rules, evolutionbeing After the moment after the Big Bang, it became widely accepted by the astronomical community, if only because it takes advantage of laws and observations that have proven their validity over the years, in various fields of physics and astrophysics. Let's find out the meaning of the phrase “We are children of the stars”.

Primordial universe

In youth Primordial universe Expanding and cooling slowly, the only elements present were hydrogen, helium, and traces of lithium. The latter was formed in the first three minutes, when the hydrogen nuclei were so close together and so hot that, just as inside stars, they merged through nuclear processes to form the two heavier elements. These three minutes, exactly three minutes, were very important. If the conditions suitable for nuclear fusion lasted even for only ten minutes, the universe would be filled with heavy elements. Almost all of the hydrogen would have disappeared, and the birth of stars, galaxies, and life itself would have been impossible. After this initial stage called primordial nucleus synthesis, the great sea of ​​matter will not undergo chemical modifications for hundreds of millions of years. Therefore, at that time, there were no other elements in the periodic table: neither oxygen, nor nitrogen, nor carbon, which is the basis of all organic molecules and life as we know it. But there wasn't even silicon and iron, essential elements for creating a rocky planet on which life could find fertile ground. to'being He chose simplicity, leaving the task of masonry to his first brick Seed space Heavy elements.

the The first giant stars Born from this pristine sea of ​​hydrogen and helium, even before they united into galaxies, it was hundreds of times larger than the mass of the Sun, and in its extremely hot core, rapid fusion processes began to generate all the elements, even iron. . As we learned from previous pages, when iron is involved, fusion processes require more energy than they can produce: the star first collapses and then rebounds and explodes like a supernova. What is not said is that in the short supernova phase all the elements of the periodic table heavier than iron are produced: copper, zinc, silver, gold, platinum, iridium, uranium and many others. As the star is dismembered, these elements are scattered into space along with the elements that have already been produced, including oxygen, carbon, nitrogen, and silicon. Enrichment of interstellar gas with new chemical species.

Population ii

The second generation of stars, which astronomers call Population II, already had a notable amount of heavy elements available. The life cycle of the most massive elements has followed in the steps of their predecessors, generating further quantities of heavier elements which are then collected by stars of later, younger populations, including the Sun. From the periodic table except hydrogen and helium came out of nothing To 2% of the chemical composition of the universeIt is an amount more than enough to assemble planets and complex molecules, until life is born. Therefore, every atom in our body, except hydrogen, was created in the nucleus of some now extinct star, in what part of the universe we know.being And at any time. All silver and gold jewelry comes from the explosion of millions of ancient stars that far exceed the mass of the sun.

More than 4.6 billion years ago, this mixture of metals, hydrogen and helium came together again to form the sun, planets and life. On that blue dot called Earth. We are stardust who at a certain point decided to come together and form beings capable of thinking and understanding the wonderful mechanism of this universe. But it is just a moment, a minor disruption in the long history of the universe. The atoms that make up our bodies and give life to ideas are merely a loan that will then be returned to the universe, which will use it. To continue his amazing adventure.

For more information, we recommend Daniele Gaspari's book: In the mind of the universe

Article in collaboration with Daniel Gaspari: https://www.astroatacama.com/