What is the big bang theory?

1. What is the big bang theory? Big Bang Intro

2. Origin of the EarthTheory that the universe began with a tremendous explosion. Beginning of time and space. 13.7 billion years ago all the contents of the universe was compressed under extreme pressure, temperature, and density in a very tiny spot called singularity. Gravity could not hold the pressure thus began the big bang. The universe rapidly expanded and matter began to come together to form galaxies. Space and time did not exist before the Big Bang

3. Origin of the Earth

4. Each object in the universe is part of a cluster or galaxy which can include planetary systems such as our solar system.We live in the Milky Way which has hundreds of billions of stars and enough gas & dust to make billions more. It also has dark matter all held by gravity. Galaxy intro

5. How did our solar system form? • Formed from clouds of gas and dust called interstellar clouds or nebulas in constant counterclockwise movement. • When the constant balance of gravity & pressure becomes upset, small regions of the nebula collapse inward increasing the temperature. • When this cloud condenses as a result of gravity, it becomes concentrated enough to form stars and planets. The dense concentration in the center of this cloud became the sun. planet formation

6. The sun contains 99.8 percent of the mass of the entire planetary system. • Mainly hydrogen • The hydrogen atomic nuclei merge into helium in the core. • This nuclear fusion is the energy source of the sun and is what heats and lights the earth.

7. It took 10 million years for the solar system to form. • The solar nebula flattened into a rotating disk of bits of dust. Some particles collided and formed bodies called planetesimals. • The largest planetesimals formed near the outside of the solar disk where hydrogen and helium were abundant. These became the gas planets Jupiter, Saturn, Uranus, and Neptune • Temperatures closer to the disk were too hot for gases to remain so the inner planets are made mostly of rocky material. Mercury, Venus, Earth, and Mars

8. How was the Moon Formed? • 4.5 billion years ago • Planet Thea hit the Earth to create the moon • Sunny side gets to 273 degrees Fahrenheit • Dark side gets to -243 degrees Fahrenheit Moon Formation

9. Kepler’s 1st Law of Motion: Law of Ellipses Planets move in an elliptical path around the Sun. Circular when the foci are close together Elliptical when the foci are further apart. Flattening is eccentricity Circle= zero

10. Kepler’s 2nd Law of Motion: Law of Equal Areas Planets move faster when they are closer to the sun and slower when they are farther away. Interactive

11. Kepler’s 3rd Law of Motion: Law of Harmonies Planets that are more distant from the sun, take longer to orbit the sun. Interactive

12. What causes the earth to be fatter at the equator? It is not a perfect sphere(Circumference around equator is 42.72 km or 25.54 mi. larger than at the poles.) An equatorial bulge is a difference between the equatorial and polar diameters of a planet, due to the centrifugal force of its rotation. A rotating body tends to form an oblate spheroid rather than a sphere.

13. Precession: The Earth's rotation axis is not fixed in space. Like a rotating toy top, the direction of the rotation axis executes a slow precession over a period of 26,000 years • All rotating bodies display precession. (tops) • The 26,000 year precession causes the sun's position to be a little different each year since the earth’s axis points in a different direction.

14. Nutation-a small irregularity in the precession of the equinoxes. (18.6 years) Changes the location of major latitude circles, slight change in seasonal effects.

15. Barycenter: The point in space around which two objects orbit Barycenter

16. Fission vs. Fusion Fusion (together) Nuclei collide and fuse forming heavier elements and enormous amounts of energy. Fusion of hydrogen to helium in the core of the sun. Fission (apart) A neutron is aimed at the nucleus of a large unstable atom like Uranium. The extra mass causes its radioactive nucleus to split forming lighter elements, energy, and free neutrons which start the chain reaction fission vs fusion Radioactive decay Occurs in the core of the sun Occurs in the core of the Earth Earth’s source of external energy Unable to use for energy Used for Nuclear power

17. Rotations

18. Moon Phases: Waxing Crescent SUN Full Moon Waning Crescent