Scientists have identified the largest sulfur-containing organic molecule, 2,5-cyclohexadiene-1-thione, ever detected in interstellar space, a discovery hailed as a "missing link" in understanding the cosmic origins of life's chemistry. This 13-atom molecule, found in the molecular cloud G+0.693–0.027 near the Milky Way's center, approximately 27,000 light-years from Earth, bridges the gap between simple interstellar chemistry and the complex building blocks of life found in comets and meteorites. Sulfur is a crucial element for life on Earth, forming amino acids and proteins, and its scarcity in large interstellar molecules had been a puzzle. The detection, made possible by radio telescopes and precise molecular "radio fingerprints," suggests that more complex sulfur-bearing molecules may exist in space, potentially indicating that biologically important materials are widespread.