Officer of the Deck
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The OOD, or Officer of the Deck monitors the CIC's operation in the absence of the ship's commanding officer. The OOD generally carries out or relays the command officer's standing orders.
In the absence of a command officer, the OOD has the conn, but typically calls the commanding officer before taking any action if time allows.
Another term for the OOD is the watch officer. Aboard Galactica, this function is usually carried out on screen by Lieutenant Gaeta, the Senior Officer of the Watch.