The molecule factory

In 1952, Miller and Urey were the protagonists of one of the boldest scientific experiments on the origin of life. They were the first to ever test whether life could have risen from a mixture of inorganic compounds, in the presence of energy. They recreated such conditions in their laboratory: an "inorganic soup" with electrical sparks passing through it. Quite extraordinarily, some organic molecules formed, the building blocks of proteins: the amino acids. It was a first, fundamental step, but what led from amino acids to life is still a mystery.