IN THE BEGINNING - cont.

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The three cosmologists accepted the observations that showed the universe to be expanding. They argued that matter was being created continuously to take the place of the matter in the receding galaxies. (Otherwise, the universe would become less dense as the galaxies moved away and occupied ever greater volumes).  Thus, by the time the distance between two galaxies doubled, enough material would have to be created to form a new galaxy.
Steady-State Universe

       The rate needed was almost vanishingly small—a couple of atoms in every cubic mile every year, or about one-thousandth of an ounce in the entire volume of Earth during its whole history.

       For the steady-state model to work, however, it had to come up with an alternative way to make all the elements we see around us. The theory’s supporters looked to the interiors of stars for the chemical factories. And they found them. These stellar cauldrons, where temperatures soar to tens of millions of degrees, generate energy by constantly fusing hydrogen into helium.
 
Learn more about:

                    Fred Hoyle

The Steady-State Universe

The Big Bang

  Formation of Elements

       The energy produced, which eventually works its way to the surface and gets emitted as light, balances the inward pull of gravity to keep the star stable. Eventually the star runs out of hydrogen fuel, however, and gravity starts to crush the core, raising the star’s internal temperature. After a while, this triggers new fusion reactions, creating carbon, oxygen, and the other elements essential to life. For the largest stars, this process continues until iron forms in the core. But fusing iron requires more energy than it produces, so the reactions can no longer hold off the inward pull of gravity. The core then collapses, causing the star to explode and spew its heavy elements back into the galaxy, where they can be incorporated into future generations of stars, planets, and perhaps even life.
 

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