ASTR 1150 Lecture Notes - Lecture 11: Virgo Supercluster, Virgo Cluster, Great Attractor
Document Summary
Astr 1150- lecture eleven: galaxy properties and mergers. Ratio of a galaxy"s mass to its luminous output. Mass to light ratios are greater than i. Most bodies are small and do not emit much light. Dark matter adds mass but no luminosity. Mass to light ratio describes age of a galaxy. Higher m/l means older stars (why does this make sense?) For spirals, mass to light ratios are between 2-10. However, there is about 10x more dark matter. Also around 100 when including dark matter. Groups of galaxies containing spirals, ellipticals and irregulars. Our galaxy is in a cluster called the local group. Local group is about 12 million ly across. Nearest neighbouring cluster is the virgo cluster. Both virgo cluster and local cluster are being attracted by a large amount of dark matter. Might be a large galaxy cluster, but there is some debate. Bluster of galaxies also tend to cluster.
