ASTRO 102 Chapter Notes - Chapter 1: Ecliptic, Virgo Supercluster, Big Bang
Document Summary
Chapter 1 - a modern view of the universe. Earth solar system milky way galaxy local group local supercluster. Solar system - consists of the the sun, the planets and their moons, and other objects. Milky way galaxy/galaxy - a great island of stars in space, all held together by gravity and orbiting a common center. Local group/galaxy clusters - groups of galaxies with many more large members. Superclusters - the regions in which galaxies and galaxy clusters are most tightly packed. Astronomical unit (au) - earth"s average distance from the sun = 150 million kilometers. Light year (ly) - the distance that light can travel in 1 year = 10 trillion kilometers. The time it takes light to travel in light years, is how we see the image of that object x amount of years ago. E. g. , planet that takes 8 light years to be seen from. Earth, is how the planet looked like 8 years ago.