The State of Our Universe

In this third year of his Gresham lectures, Chris Lintott returns to the big questions which make up modern astrophysics, taking us from the search for life elsewhere in the Solar System and in the galaxy to the grandest of cosmological mysteries. At a time characterised by both great progress and great uncertainty in how to make further progress, it is the perfect time to take stock of the state of the Universe and of our understanding of it. The lectures draw on fresh data from modern instruments and spacecraft, in particular the Vera Rubin Observatory, now starting the largest and deepest survey of the sky ever undertaken, with the fifth lecture in the series devoted to the first results from this grand endeavour. The last lecture, a coda to the series, explains why Pluto isn’t a planet, why this doesn’t matter, and how we should think while contemplating a vast cosmos both more alien and more familiar than we might once have anticipated.