A BIG BANG, THEN, LET THERE BE LIGHT, THEN, LET THERE BE LIFE.

VERN BENDER

4 years ago

The Big Bang: 10^-43seconds. The universe begins with a cataclysm that generates space and time and all the matter and energy the universe will ever hold. For an incomprehensibly small fraction of a second, the universe is an infinitely dense, hot fireball.
At 10^-35to 10^-33seconds, a runaway process called “Inflation” causes a vast expansion of space filled with this energy. The inflationary period is stopped only when this energy is transformed into matter and energy as we know it.
The Universe Takes Shape: 10^-6 seconds old. After inflation, one-millionth of a second after the Big Bang, the universe continues to expand but not nearly so quickly. As it grows, it becomes less dense and cools. The most fundamental forces in nature become distinct: first gravity, then the strong force, which holds nuclei of atoms together, followed by the weak and electromagnetic forces. By the first second, the universe comprises fundamental particles and energy: quarks, electrons, photons, neutrinos, and less familiar types. These particles smash together to form protons and neutrons.
Formation of Basic Elements: 3 seconds old. Protons and neutrons come together to form the nuclei of simple elements: hydrogen, helium, and lithium. It will take another 300,000 years for electrons to be captured into orbits around these nuclei to form stable atoms.
The Radiation Era: 10,000 years old. The first significant era in the universe’s history is when most of the energy is in the form of radiation — different wavelengths of light, X rays, radio waves, and ultraviolet rays. This energy is the remnant of the primordial fireball. As the universe expands, the waves of radiation are stretched and diluted until today; they make up the faint glow of microwaves that bathe the entire universe.
I am beginning the Era of Matter Domination:300,000 years old. At this moment, the energy in matter and the energy in radiation are equal. But as the relentless expansion continues, the waves of light are stretched to lower and lower energy, while the matter travels onward largely unaffected. At about this time, neutral atoms are formed as electrons link up with hydrogen and helium nuclei. The microwave background radiation hails from this moment and gives us a candid picture of how the matter was distributed at this early time.
Birth of Stars and Galaxies: 300 million years old. Gravity amplifies slight irregularities in the density of the primordial gas. Even as the universe continues to expand rapidly, pockets of gas become denser and denser. Stars ignite within these pockets, and groups of stars become the earliest galaxies. This point is still perhaps 12 to 15 billion years before the present.
Gravity. No stars, no planets, no life!
After protons and neutrons are bound together into nuclei and atoms, these nuclei are surrounded by a full complement of electrons. Helium, hydrogen, and carbon atoms dominate until the heavier elements show up. The heavier elements, such as iron, lead, and uranium that contain ever-larger numbers of protons, neutrons, and electrons, show up.
Roughly 380,000 years after the Big Bang, matter cooled enough for atoms to form during the era of recombination, resulting in a transparent, electrically neutral gas, atoms began creating.
The “let there be light” time was at hand.
A billion years later, galaxies proliferated across the cosmos. When stars start exploding, the heavier elements began to be dispersed.
The birth of our sun was about 4.6 Billion Years ago. The birth of our planet is estimated to be 4.54 billion years old, plus or minus about 50 million years—the sun forms within a cloud of gas in a spiral arm of the Milky Way Galaxy. A vast disk of gas and debris that swirls around this new star gives birth to planets, moons, and asteroids. Earth is the third planet out.
The earliest Life forms on earth were 3.8 Billion Years ago. The Earth has cooled, and an atmosphere had developed to support life.
Primitive Animals Appear: 700 Million Years ago. These are primarily flatworms, jellyfish, and algae. By 570 million years before the present, large numbers of creatures with hard shells suddenly appear. (THE CAMBRIAN EXPLOSION).
A SUPERNOVA EXPLODES IN OUR NEIGHBORHOOD IN 1987. A star explodes in a dwarf galaxy known as the Large Magellanic Cloud that lies beyond Milky Way. It is a blue supergiant 25 times more massive than our Sun. Such explosions distribute all the typical elements such as Oxygen, Carbon, Nitrogen, Calcium, and Iron. They enrich clouds of Hydrogen and Helium that are about to form new stars. They also create heavier elements (such as gold, silver, lead, and uranium) and distribute them.