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Two astrophysicists have finally solved a 20-year-old astrophysical puzzle concerning the lower-than-expected amounts of the element sulphur found in Planetary Nebulae (PNe) in comparison to expectations and measurements of other elements and other types of astrophysical objects. The expected levels of sulphur have long appeared to be ‘missing in action’. However, they have now finally reported for duty after hiding in plain sight, as a result of leveraging highly accurate and reliable data.