The document discusses the origin and fate of the universe. It provides a timeline of cosmic events from the formation of hydrogen and helium nuclei shortly after the Big Bang to the formation of our solar system around 4.6 billion years ago. It also explains that the ultimate fate of the universe, whether it expands forever or contracts back into a "big crunch", depends on the total mass of the universe and its interaction with gravitational forces.

1. The Origin and the Fate of the Universe 1.1f No Excuses, Just Results! Show-up, Engage & Produce

2. Meaningful Class Participation and Effort

3. ACHIEVE South High School

4. The Red Shift No Excuses, Just Results! Show-up, Engage & Produce

5. Timeline of the Expanding Universe 10-6 Hydrogen and helium nuclei form (100 sec. after the big bang) 10-4 10-2 100 10 102 104 106 108 First atoms form First galaxies form 1010 Our solar system form Present (15 billion years) No Excuses, Just Results! Show-up, Engage & Produce

6. Fate of the Universe depends on mass If there is not enough mass in the universe, the gravitational force will be too weak to stop the expansion, so the universe will expand forever. No Excuses, Just Results! Show-up, Engage & Produce

7. Fate of the Universe depends on mass If there is just the right amount of mass, the expansion will continually slow down but never stop completely. No Excuses, Just Results! Show-up, Engage & Produce

8. Fate of the Universe depends on mass If there is more mass, gravity will eventually win out over the expansion and the universe will start to contract until it collapses back to a “big crunch”. No Excuses, Just Results! Show-up, Engage & Produce