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Surprising progress occurred in observational astronomy during World War II, despite the calling of many astronomers for service in the war effort. In the midst of assignments from the military Office of Scientific Research and Development and consulting for the Eighth Air Force in England, Gerard Peter Kuiper found time for “pure” research. The January 29, 1944, Science News Letter published a summary of the evidence that led him to believe that Titan had an atmosphere: methane (marsh gas) and possibly ammonia had been discovered in its spectrum. Thus, Titan became the first satellite demonstrated to have an atmosphere, a primacy that lasted thirty years, until space probes gave information about the thin atmospheres of Ganymede, Callisto, and Io, Jupiter’s large satellites.