How do we know that the Universe is expanding? Describe Hubble′s law, and the types of measurements that need to be taken in order to measure the Hubble constant. – Describe standard candles (cepheid variables) and how they are used for these measurements. – How does invoking Big Bang explain the fact that the Universe is expanding? – How can we estimate how old the Universe is, from its current expansion rate? – Optional — current experiments aimed at measuring the Hubble constant with extreme precision
