Presentation on theme: "What are Galaxies? Galaxies are large systems of stars and interstellar matter(planets, moons, asteroids, etc.) typically containing several million to."— Presentation transcript:
What are Galaxies? Galaxies are large systems of stars and interstellar matter(planets, moons, asteroids, etc.) typically containing several million to trillions of stars. They are held together by gravity! Most galaxies are several thousand light years in width
Types of Galaxies 1.Elliptical Galaxies are oval to round in shape most are made up of a few million stars. More common than irregular but less common than spiral They contain the oldest stars with very little dust and gas (nebula).
Types of Galaxies 2. Spiral Galaxies Contain between a billion and a trillion stars. They typically have two main spiral arms curling out of a bulging center. They contain many middle-aged stars along with nebula. Most common type of galaxy The Milky Way is a spiral galaxy.
Types of Galaxies 3. Irregular Galaxies Do not fit into the spiral or elliptical groups. Their shapes are undefined. Least common type of galaxy Most irregular galaxies contain young stars, and much nebula..
Milky Way Galaxy It is a spiral galaxy Contains between 200 to 400 billion stars…. Maybe even a trillion! Middle aged It’s width is 100 thousand light years It takes the solar system 240 million years to make one full orbit You are here
The Milky Way Galaxy! The Core of Milky Way Galaxy Milky way
What is the Universe? The Universe is most commonly defined as everything that physically exists! It is comprised of billions of galaxies. What are galaxies?
The Universe Even though the stars look close together in space. Space is relatively empty. If a dozen tennis balls were spread out across the USA, they would be more crowded than most stars in Universe.
My Universal Address! Jeremy Arend 109 Tar Heel Drive Delaware, OH United States Earth Solar System Milky Way Galaxy Universe Where do you live?