Stars with masses greater than ten times that of the Sun live very short and dramatic lives compared to their less massive siblings. Some of the most massive stars have lifetimes of less than a few million years before they exhaust their nuclear fuel and explode as supernovae. An international team of astronomers has observed part of the final death throes of W26, the largest known star in the Universe, as it throws off its outer layers. W26 is a Red Super Giant and has a radius 1500 times larger than the Sun. The discovery is a vital step in understanding how massive stars return enriched material to the interstellar medium -- the space between stars -- which is necessary for forming planetary systems.