Comedian, theoretical physics grad and mathematics enthusiast Dara Ó Briain (@daraobriain) joins Matt and Andy to discuss stages of mathematical rigor, Évariste Galois, Catalina bison, Dara's new obsession with astrophotography from his London garden (examples of which are here and here), Andy's crappy cell phone moon pic and this podcast's new mission to help Dara get to Bortle 1.

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