Does Pluto have an atmosphere? Two recent occultations give perplexing results. (See the Sky and Telescope article.) Perhaps the answer will have to wait for the New Horizons mission to visit Pluto (the only planet not visited by robotic explorers). Of more interest on this mission is a exploration of Kuiper belt, the source of shoty period comets (like the 76 year Halley's comet). Given the potentially cataclysmic consequences of an errant comet, one might suppose that the more that is known by these occaisional visitors, the better.