What is it and how did it all begin? Universe Creation What is it and how did it all begin?

The Universe Milky way galaxy is part of 20 other galaxies.

Solar System Sun is a star – hot ball of plasma that shines because of nuclear fusion taking place Nulcei of atoms fusing together to make larger atoms. AU – Astronomical Unit Distance between sun and earth (150 million km) Light years (ly) = 63000 AU or 9.0 x 1012 km Inner Solar system Mercury, Venus, Earth and Mars Outer Solar system Asteroid belt (3AU) and 4 giant gas planets Jupiter, Saturn, Uranus and Neptune

Stars Supernova – exploding stars after millions or billions of years of build up of heavy elements at the stars core Nebula – large cloud of dust and gas that remains after a supernova. About 1 supernova a week is determined by humans

Properties of Galaxies Black Holes – region of space in every galaxy where gravity is so strong that nothing can escape Dark Matter – matter in the universe that is invisible because it does not interact with light or any other type of radiation Instead of the Milky way spinning out matter and coming apart, it is being kept together by the gravitational force of an enormous amount of matter that we can not see directly.

Expanding Universe Big Bang – universe formed when an infinitely dense point suddenly and rapidly expanded in a single moment. Spectral lines – created as each gas that makes up a star absorbs some of the light energy

Expanding Universe All other galaxies are moving further away at a faster and faster rate. Animation Red Shift vs. Blue Shift Cosmic Background Radiation – short waved gamma radiation shifting to x-rays, infrared and microwaves…discovered in 1965 It is now commonly accepted that the universe is about 13.7 billion years old