Its existence was first speculated to explain the rate at which the universe is expanding. Dark energy, together with dark matter, makes 95% of the universe - yet we have little idea of what it is. According to one theory, dark energy is a particle, linked to a fifth fundamental force, a theory that was yet to be supported by experimental evidence. However, a new study led by researchers at the University of Cambridge and Frascati National Laboratories suggests that an experiment originally designed to detect dark matter might have in fact detected dark energy. If further supported by other experiments, this finding will hail a new era in our understanding of what the universe is made of, illuminating what lies beyond the standard model of particle physics, and giving us an insight into what the universe’s fate might ultimately be, writes Sunny Vagnozzi, a Cambridge researcher and co-author of this new study.