1. The Big Bang! (pg 20)

2. Origins How did the: How did the: Universe form? Universe form? Solar system / Earth form? Solar system / Earth form? How Do We Know?

3. Origin of the Universe Big Bang - model for beginning of the universe Big Bang - model for beginning of the universe ~15 billion years ago ~15 billion years ago Expansion from a hot dense state into a vast much cooler cosmos Expansion from a hot dense state into a vast much cooler cosmos

4. What did it look like? Expansion from a hot dense state into a vast much cooler cosmos

5. http://rainbow.ldeo.columbia.edu/courses/v1001/7.html - infinitely dense point not governed by our physical laws or time - all matter and energy contained in one point Building a Universe

6. http://rainbow.ldeo.columbia.edu/courses/v1001/7.html Instantaneous filling of space with all matter As matter filled space it began to rapidly cool. Building a Universe As things cool they move from gas to liquid to solid. Think about water as it cools from steam to water to ice.

7. Continuing expansion

8. Edwin Hubble: Evidence of the Universe continuously expanding Doppler shifting - wavelength emitted by something moving away from shifts to a lower frequency – or Red Light Visible wavelengths of light emitted by objects moving away from us are red The faster the object is moving, the redder the light THE DOPPLER EFFECT

9. Hubble’s Evidence – The Red Shift caused by the Doppler effect When we observe distant galaxies, they appear to give off red light. This means they are moving away from us = universe is expanding. The faster they move away from us, the more they are red shifted. We can measure the speed of an object by the wave length it emits This is the principal by which radar guns measure the speed of a car or baseball Sound of a fire truck siren - pitch of the siren is higher as the fire truck moves towards you, and lower as it moves away from you

10. Where else to you HEAR the Doppler effect? Sound of a police car’s siren Pitch of the siren is higher as the fire truck moves towards you, and lower as it moves away from you

11. Features of Our Solar System Orion Spiral arm of the Milky Way Galaxy Our Sun and our 8 planets (sorry Pluto) 172 known moons (satellites) orbiting planets or other objects (dwarf planets) 2 Different asteroid fields One is in orbit the Sun between the orbits of Mars and Jupiter and the other is the Kuiper belt at the edge of the solar system Interplanetary dust and gases A huge amount of Comets (from the Kuiper belt, mainly)

12. Relative Sizes of the Sun and Planets

13. Solar System Configuration

14. Origin of Our Solar System

15. Solar nebula theory The cloud begins to rotate and forms a disk. The rotation causes gravity to get intense. The cloud begins to rotate and forms a disk. The rotation causes gravity to get intense. Gravity causes the matter in the cloud to condense and eventually collapse creating immense pressure. Gravity causes the matter in the cloud to condense and eventually collapse creating immense pressure. A solar nebula is formed A solar nebula is formed There is an embryonic Sun at the center There is an embryonic Sun at the center A rotating cloud surrounds the sun A rotating cloud surrounds the sun Cloud of gases and dust Cloud of gases and dust

16. large currents of gas and dust remain far from the protosun (the center) Embryonic Sun and Rotating Cloud planetesimals have formed in the inner solar system

17. The Planets Terrestrial Planets: small, composed of rock, with metal cores Terrestrial Planets: small, composed of rock, with metal cores Mercury Mercury Venus Venus Earth Earth Mars Mars Jovian Planets: large, composed of hydrogen, helium, ammonia, methane, relatively small rocky cores Jovian Planets: large, composed of hydrogen, helium, ammonia, methane, relatively small rocky cores Jupiter Jupiter Saturn Saturn Uranus Uranus Neptune Neptune – Pluto?

18. Review

19. Review When did the Universe begin? When did the Universe begin? What is the name of the theory describing how the universe began? What is the name of the theory describing how the universe began? What happens to the temperature of matter (gasses, liquid, etc.) as it expands? What happens to the temperature of matter (gasses, liquid, etc.) as it expands? Describe the universe just before the big bang. Describe the universe just before the big bang. How can we tell the universe continues to expand? How can we tell the universe continues to expand? Give an example of where you can see or hear the Doppler effect. Give an example of where you can see or hear the Doppler effect. What occurs in each of the three steps in the Nebular Theory? What occurs in each of the three steps in the Nebular Theory?