AS101 Lecture Notes - Local Group, Virgo Supercluster, Interstellar Cloud
Document Summary
Galaxy: a large group of stars in space, all held together by gravity and orbiting a common center. 100 billion stars are in the milky way galaxy. Nebula: an interstellar cloud of gas and/or dust. Cluster: a group of galaxies all held together by gravity. The milky way galaxy is part of the local cluster. The local cluster is part of the local supercluster. These are the largest known structures in the universe. The universe is made up of all matter and energy within and in between galaxies. Matter and energy can interact with each other, and can also be converted from one to another. The actual distance to alpha centauri is roughly 44 trillion km =
