How pigeon droppings nearly derailed a massive discovery in cosmology

Great cosmology research requires accounting for an enormous number of variables, everything from nuclear detonations to bird droppings. In this animation from Nature, the American radio astronomer Robert Wilson discusses how a pair of pigeons living in a large antenna frustrated attempts to measure the minimum brightness of the sky. Even once the pigeons were removed, the measurements still weren’t right. The issue, it turned out, was cosmic microwave background radiation left behind by the Big Bang – a discovery that would eventually earn Wilson part of the 1978 Nobel Prize in physics.