Astronomy 1021 Chapter Notes - Chapter 1: Naked Eyes, Dark Energy, Edwin Hubble
11 Oct 2017
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Document Summary
Our cosmic address: the address that we are located in the universe. Earth, solar system, milky way galaxy, local group, local supercluster, universe. Earth is a planet in our solar system, which consists of the sun, the planets and their moos, and rocky asteroids and icy comets. Our solar system belongs to the disk-shaped collection of stars called the milky way. A galaxy is a great island of stars in space, containing lots of stars. The milky way contains more than 100 billion stars. Billions of other galaxies are scattered throughout space. The milky way is one of the two largest among 70 galaxies (approximately) in the local group. Groups of galaxies with more than 12 large members are often called galaxy clusters. Galaxies and galaxy clusters appear to be arranged in giant chains and sheets. The regions in which galaxies and galaxy clusters are most rightly packed are called superclusters.
