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Radio Waves

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Science Competition

Space Timeline

This below is my timeline of space it should explain the many theories of how the universe came to be. It should explain about how galaxy was formed and what stage our star; the sun is in at this point in this present moment. The Time Line will take you from the moment it was created to the moment it will die. It will show each step in as much detail as I can find.

The Big Bang Theory

I am going to start the timeline with the big bang theory as people/scientists believe that it was at this point at which our universe was created

The diagram below shows the early stages of the universe after the big bang. I am going to show you step by step how each stage happened and what it meant. The short section of the timeline below shows the short period of time, 300 million years after the big bang.

Stage 1 The Big Bang-The universe began with an explosion that generated space and time, as well as all the matter and energy the universe has and will ever hold. For a small fraction of a second, the universe was an infinitely dense, hot fireball. The present theory described a peculiar form of energy that could suddenly push out the fabric of space. On a rare occasion, a process called "Inflation" can cause a vast expansion of space filled with this energy. The inflationary expansion could only be stopped when this energy had transformed into matter and energy as we know it.


Stage 2 Universe Shaped- After inflation, one millionth of a second after the Big Bang, the universe continued to expand but not nearly as quickly as it had done. As it expanded, it became less dense and cooled down. The most basic forces in nature were discovered: first gravity, then the strong forces then the weak followed by the electromagnetic forces. By the first second, the universe was made up of elementary (basic) particles and energy basic elements such as: quarks, electrons, photons, neutrinos and less familiar types. These particles smashed together to form protons and neutrons.

Stage 3 Basic Elements Formed- 3 seconds after the universe had shaped Protons and neutrons came together to form the nuclei of simple elements such as: hydrogen, helium and lithium. It took another 300,000 years for electrons to be captured into orbits around those nuclei to form stable atoms.

Stage 4 The Radiation Era - The first major era in the history of the universe was one in which most of the energy was in the form of radiation -- different wavelengths of light, X rays, radio waves and ultraviolet rays. This energy was the remnant of the primordial fireball, and as the universe expands, the waves of radiation are stretched and diluted until today; they make up the faint glow of microwaves which bathe the entire universe.

Stage 5 Matter Domination Era- At that moment, the energy in the matter and the energy in the radiation were equal. But as the vast expansion continued, the waves of light were stretched to lower energy, whilst the matter travelled onwards largely unaffected. At about this time, neutral atoms had formed as electrons link up with hydrogen and helium nuclei. The microwave background radiation hails from this moment, and thus gave us a direct picture of how matter was distributed at this early time.

Stage 6 Stars and Galaxies Formed- Gravity amplified the slight irregularities in the density of the primordial gas. Even as the universe continued to expand rapidly, pockets of gas became more and more dense. Stars ignited within these pockets, and groups of stars became the earliest galaxies. This point was still perhaps 12 to 15 billion years before the present. The Hubble Space Telescope recently captured some of the earliest galaxies ever viewed. They appear as tiny blue dots in the Hubble Deep Field, the image on the left.

Here are some of the pictures of Galaxies I managed to find.

That concludes the first part of my timeline about the period of time after the big bang. The next part of my timeline is the period of time which was before the present time but after the Big Bang Period. The diagram below shows the period of time called Time before Present.

Stage 7 Birth of the Sun- 5 Billion years after the Big bang our Sun was born. The sun was formed within a cloud of gas in a spiralling arm of the Milky Way Galaxy. A vast disk of gas and debris that swirled around our new star gave birth to our planets, moons, and asteroids.

The image on the left was taken from the Hubble Space Telescope, showing a newborn star in the Orion Nebula surrounded by a disk of dust and gas that may one day collapse into planets, moons and asteroids. Just like our sun did 5 billion years ago.

Stage 8 Earliest Life- 3.8 million after the birth of our sun the planet earth had cooled and an atmosphere was created. Microscopic living cells, neither plants nor animals, began to evolve and flourish in earth's many volcanic environments.

Stage 9 Primitive Animals Appeared- These were mostly flatworms, jelly fish and algae. By 570 million years before the present, large numbers of creatures with hard shells suddenly appeared

Stage 10 The First Mammals Appeared- The first mammals evolved from a class of reptiles which evolved with mammalian traits (characteristics), such as a segmented jaw and a series of bones that make up the inner ear.

Stage 11 Dinosaurs Became Extinct-An asteroid or comet slammed into the northern part of the Yucatan Peninsula in Mexico 65 million years after the mammals had first evolved. This world-wide cataclysm brought the end to the long age of the dinosaurs, and allowed mammals to diversify and expand their ranges.

Stage 12 Homo sapiens Evolved- Our earliest ancestors evolved in Africa from a line of creatures that descended from apes.

Stage 13 Supernova 1987A Explodes-A star exploded in a dwarf galaxy known as the Large Magellanic Cloud that lies just beyond the Milky Way. The star, was a blue super giant/red giant 25 times more massive than our Sun. Such an explosion distributed all the common elements such as Oxygen, Carbon, Nitrogen, Calcium and Iron into space where they enriched clouds of Hydrogen and Helium which formed new stars. They also created the heavier elements (such as gold, silver, lead, and uranium) and distributed these as well. Their remnants generated the cosmic rays which lead to mutation and evolution in living cells. These



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