Jared and I have started exploring the scale of the Universe in preparation for a more full-depth study of the evolution of the Universe following the Big Bang. We discussed the fact that lightyears are in fact units of length (and not time), and we looked at the the size of the Milky Way in terms of lightyears. I also introduced Jared to the 'parsec', the basic unit of distance used in astronomy (outside of the Solar System), and showed how it relates to the lightyear.