NEIGHBOURHOOD WATCH A tour of our local galactic group

We used to think we lived in an ‘island universe’ consisting only of our Milky Way. However, many of the faint smudges once called nebulae turned out to be other ‘island universes’ too, our view of the Universe being fundamentally altered in 1924 when Edwin Hubble proved they were galaxies much like our own. As time went by, we found these galaxies liked to form groups and it was quickly observed that we were part of one, which was imaginatively named the ‘Local Group’.

Our galactic neighbourhood includes two spiral galaxies (the Andromeda Galaxy, M31, and the Triangulum Galaxy, M33); two satellites of our Milky Way (the Large and Small Magellanic Clouds); the companion galaxies to M31; and several outlying galaxies (NGC 185 and 147), along with dozens of dwarf galaxies too faint for us to view. From the Northern Hemisphere at this time of year, several of the major members of our Local Group can