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Galactica has an astrometrics area, which is equipped with spectroscopic instruments, as well as optical and x-ray telescopes. The instruments are used in FTL navigation to acquire star fixes for jump computations, and to search for celestial objects that could be used as resources to keep the Fleet supplied with necessary goods such as food and water.
Colonel Saul Tigh reports that the astrometrics team detected five planetary bodies within practical jump range with the potential to contain water when the ship and her charges are in danger from a water crisis (TRS: "Water").
Lieutenant Felix Gaeta often uses astrometric resources (particularly spectroscopy) in his analysis of information garnered from the Fleet's encounters of waypoints to Earth, such as the Lion's Head Nebula and the Eye of Jupiter (TRS: "Torn", "The Eye of Jupiter", "Rapture").
It is probable that astrometrics played a large role in the initial remote detection of a planetary body, located just outside a dangerous star cluster with food resources desperately needed by the Fleet during a food crisis (TRS: "The Passage").