Most of the elements that populate the universe (and our periodic table) come from massive cosmic explosions. One such explosion, a kilonova, produces many elements heavier than iron. Including a large amount of gold in the universe. However, for a kilonova to occur requires precisely this scenario: the collision of two neutron stars, the extremely dense remnants of stars that died in supernovae. What is the origin story of these collisions? A study, the first of its kind, published in the journal Nature, showed that a star system within the Milky Way galaxy will perish in a massive cosmic explosion (kilonova). Known as CPD-29 2176, this star system is 11,000 light-years away from Earth in the outskirts of the Milky Way. It consists of a neutron star that completes a circular orbit in 60 days around a hot, rotating star 18 times more massive than the Sun (Fig. 1). Astronomers estimate that there are no more than ten such systems in our galaxy today. This makes the system (CPD-29 2176) a 1 in 10 billion discovery. Over the next few million years or so, the gravity of this system’s neutron star will dissipate and eject most of the mass of the partner star. The partner will then die in a supernova (2), the remnants of which will form a second neutron star (3). Over another billion years, these two neutron stars will spiral inside each other (4) until they merge and cause a kilonova explosion (5). The mixture of newly formed heavy elements in the followingmath of this galactic explosion will look like confetti scattered in space.