At the onset of the Big Bang event, there were no atoms. The only physical items were tiny particles that would someday combine to make atoms. These tiny particles are called subatomic particles.
According to scientists, when the Big Bang occurred, it was too hot for atoms to form. As each second ticked by, the temperature dropped very fast. Within 3 minutes of the Big Bang, the heavier particles combined to form what are called protons and neutrons. These would later combine with electrons to produce the most simple atoms, hydrogen and helium.
Since there was an abundance of particles that would combine to produce simple atoms, then the Big Bang theory predicts that there should be an abundance of hydrogen and helium. People who study atoms figured out that the Big Bang would produce about 75% hydrogen atoms and 25% helium atoms. This forecast comes from a good understanding of nuclear reactions due to decades of smashing atoms together in particle accelerators.
Now think of a beautiful rainbow with light separated into distinct colors; red, orange, yellow, green, blue, indigo, and violet. The bright colors are due to light separating into different colored spectrums (wavelengths). People who study atoms use instruments called spectroscopes that separate light, just like a rainbow appears.
Now think of the sun. In the sun are very hot atoms that give off light. Each atom, whether it is hydrogen or helium, gives off light (An element gives a line spectrum – one or more bright discrete lines at specific wavelengths). By using a spectroscope, scientists have found that each atom gives a unique rainbow like pattern. For instance, hydrogen gives a distinct rainbow like fingerprint. Helium will have a slightly different rainbow pattern. From the lightest atoms to the heaviest, each atom has its own distinct pattern.
If you have an unknown atom, you can find out what it is. People who study atoms just heat up the atom and see what kind of light comes out. For example, below is the light that comes from the hydrogen atom.
Notice that hydrogen has three lines, two blue and a red line. No other atom gives this type of colors.
Below is the light from a helium atom. It has nine lines of color. No other atom gives this type of colors.
By using a spectroscope to analyze light coming from the sun or different stars, we can find out what atoms are present. By analyzing the light coming from the universe (the sun, stars, and galaxies), scientists have found that the universe is made of about 75% hydrogen and 25% helium. The percentage of these atoms agrees with the predictions of the Big Bang theory.
The Big Bang theory along with our understanding of nuclear chemistry expects a greater amount of light elements such as hydrogen and helium. Theory and observation agree.
As a star burns, nuclear chemistry changes its hydrogen atoms to helium atoms. This process yields heavier and heavier elements as time passes. For sun like stars, the nuclear process ends with helium and the star eventually dies. For extremely huge stars, the process of nuclear chemistry ends when the elements combine to form iron. As the process continues in changing the material into iron, a drastic event occurs. About that time, the huge star explodes. The explosion is called a supernova. Huge stars that produce a supernova are classed as type II supernova.
Based on this process, logic tells us that eventually, the higher percentage of hydrogen will decrease. Logic tells us that the universe has not existed forever. Again, there is strong evidence that the universe had a beginning based on the nuclear chemistry inside the stars.
Let's move on. However, this time we will learn that our universe appears to have existed only one time and that it is dying.
Go to Next Page
Weird, Creepy Universe"