AS102 Study Guide - Final Guide: Cosmological Principle, Local Group, Virgo Supercluster
Document Summary
So, while the universe as a whole is expanding, space is not expanding within our solar system, our galaxy, or even our local. Our solar system is the same size it"s always been. The same can be said of our galaxy and of our local group of galaxies. It is quite likely that dark matter within a galaxy and a local group of galaxies is an essential part of the local gravity picture. In fact, our own local group is not moving away from the next closest big cluster of galaxies (the virgo cluster) as fast as. Hubble"s law predicts because of the gravitational attraction on our local group by the virgo cluster. These two clusters are part of the local supercluster (think back to the very first part of as101). When we examine the universe we find that it is isotropic and homogeneous. Isotropic means that the universe looks the same in every direction we look.
