After a two-year orbital tour around comet 67P/Churyumov-Gerasimenko, ESA's Rosetta spacecraft--carrying Southwest Research Institute's Alice ultraviolet spectrograph--will end its mission this week on Sept. 30. Rosetta is the first spacecraft to orbit and escort a comet, and Alice, developed and operated for NASA, is the first instrument to obtain far-ultraviolet observations at a comet.