How far would you travel to get away from everyone you love? Would 400,000 kilometres be enough? Damien Chazelle is not a romantic. He is in the habit of taking conventionally uplifting genres — the artist’s journey, the technicolour musical, and now the space race — cutting out their rah-rah hearts, and rebuilding them with a controlled focus on grit, sacrifice and the weight of roads not taken. The spectacular lunar leap that took place in the summer of 1969 is hardwired to be a narrative of triumph. Triumph over gravity, over the odds, and, let’s not forget, over the Soviets, who snatched an…