1. Big Bang timeline

2. Big Bang Timeline 13.7 billion years ago – Before the Big Bang, the universe was a hot point ( ) of pure energy : Tremendous levels of radiation and heat prevented particles of matter from forming.

3. Big Bang Timeline 10 - 32 sec after the Big Bang “Quark Soup” The 4 forms of energy separate leaving a superhot, charged plasma of the tiniest particles of matter: Quarks Leptons – electrons & neutrinos

4. Big Bang Timeline 10 - 32 sec – “Quark Soup”

5. Big Bang Timeline (This mess is nicknamed “Quark Soup”.) The Universe is still only the size of a tennis ball at this point, but it’s growing like crazy!!)

6. Big Bang Timeline 10 - 6 sec (1/1,000,000 sec) – 1 sec after Big Bang As the universe expands, it cools off quickly. The ambient temperature in the universe drops to a mere 1 trillion degrees… …as the Universe has expands rapidly until it reaches 80 billion miles across.

7. Big Bang Timeline 10 - 6 sec (1/1,000,000 sec) - 1 sec after the Big Bang It is cool enough that quarks collide and join to form protons & neutrons Proton Neutron

8. Big Bang Timeline These protons are the first atomic nuclei (of hydrogen atoms). Most hydrogen atoms are as old as the universe. Proton

9. Big Bang Timeline 10 - 6 sec (1/1,000,000 sec) - 1 sec ( continued) Note: At the same time: anti-quarks joined to form anti-protons and anti-neutrons.

10. Big Bang Timeline 10 - 5 sec (1/100,000 sec) (cont.) Much of the matter and all of the anti-matter annihilated each other, filling the universe with huge amounts of radiation.

11. Big Bang Timeline 10 - 5 sec (1/100,000 sec) (cont.) Much of the matter and all of the anti-matter annihilated each other, filling the universe with huge amounts of radiation.

12. Big Bang Timeline 3 sec - 20 minutes after the Big Bang Universe expands to form a thermonuclear fireball 1.3 trillion miles across! 3 sec - 20 minutes after the Big Bang Universe expands to form a thermonuclear fireball 1.3 trillion miles across!

13. Big Bang Timeline 3 sec - 20 minutes after the Big Bang Neutrons and Neutrons and protons collide and finally stick together to form Helium (He) nuclei … (held together by the strong nuclear force)

14. Big Bang Timeline 3 sec - 20 minutes after the Big Bang …(and just a handful of Lithium (Li) nuclei). Evidence: The universe is still 99.9 % H and He today.) (92.7 % H and 7.2 % He)

15. 3 sec - 20 minutes after the Big Bang Primordial Nucleosynthesis Neutrons and Neutrons and protons collide to form Helium (He) nuclei … Big Bang Timeline He

16. 3 sec - 20 minutes after the Big Bang Electrons are flying around unattached to atoms, trapping photons of light, ultraviolet and x-ray radiation and keeping the universe opaque. Big Bang Timeline opaque.

17. Big Bang Timeline 3 sec - 20 minutes after the Big Bang As the fireball expands to a couple of 1000 times bigger than our solar system: Temperatures drop below 1 billion o C for the first time.

18. Big Bang Timeline 3 sec - 20 minutes after the Big Bang These “cooler” temperatures cause fusion reactions to stop before larger elements can form. Evidence: the universe is still 99.9 % Hydrogen & Helium today!

19. Big Bang Timeline 380,000 years later - Temperature drops to 3000 o C. The universe had grown a lot, but it was still 1000 X smaller than it is today.

20. Big Bang Timeline 380,000 years later - Temperature drops to 3000 o C. Electrons slow down…

21. 380,000 years later - …and start to orbit the atomic nuclei to make atoms of hydrogen, helium and lithium. Big Bang Timeline Helium Lithium

22. Big Bang Timeline 380,000 years later – continued Matter and energy decouple (separate from each other) as atoms form. Photons of light and neutrinos stopped interacting with electrons and are no longer “trapped”.

23. Big Bang Timeline 380,000 years later – continued This decoupling released huge amounts of gamma rays and cosmic rays. Decoupling also cleared up the universe, which became transparent. transparent

24. Big Bang Timeline – continued 380,000 years later – continued This high energy radiation has cooled off to become the cosmic background microwave radiation still seen today.

25. Big Bang Timeline 380,000 years later – continued cosmic background microwave radiation 1967 - discovered by Penzias and Wilson Studied in greater detail, first by the COBE and more recently by the WMAP space exploration projects. These images show the universe as it appeared 13.7 billion years ago. (See next frame.)

26. Cosmic Background Microwave Radiation (WMAP Satellite Shows a More Detailed Image) COBE WMAP

27. Big Bang Timeline 1 Billion Years Later (12.7 b.y. ago) Gravity causes clouds of H and He condense into lumpy pockets called galaxies (about 100 billion of them!). (The pockets of intense radiation on the WMAP are thought to be the sources of the first galaxies.) Deep Field Telescope View of the Early Galaxies

28. Big Bang Timeline 3 Billion Years After the Big Bang… Within each galaxy, smaller balls of H and He gas were pulled inward by gravity. Heat from the gravitational compression caused thermonuclear reactions and the first stars were formed. The first stars were entirely Hydrogen & Helium.

29. Big Bang Timeline 9.1 Billion Years After the Big Bang (4.6 billion years ago) Earth’s Sun and Solar System formed after 750 generations of stars had come and gone.

30. 9.1 Billion Years After the Big Bang… (4.6 billion years ago) (Our sun is made up of a lot of “recycled” parts from earlier stars, not just H & He, but Li, C,O, Na, Ca, Fe and many others. Big Bang Timeline

31. Pure Energy “Quark Soup” He & Li Nuclei Atoms Form The Skies Clear… Today 10 -6 sec 1 st Protons (H Nuclei) & Neutrons 3 min 380,000 years First Galaxies First Stars 3 Billion Years 13.7 Billion years Our Sun 9 Billion Years

33. Not Enough Matter Just Enough Matter Too Much Matter Matter & the Fate of the Universe

34. A Stanmo Production Thanks to NASA and JPL for the great pix. 2008