Gaps are the intervals of useful observing time during which no useful activities are scheduled.
Non-useful observing time includes FGS earth avoidance time, FGS SAA passage time, and major vehicle slews. All activities related to proposals on the optional list will be considered not useful. Gaps are any periods during useful observing intervals greater than 5 seconds duration during which no useful activities are taking place. Useful observing time is by definition all other time during the week. These files contain the same information contained in GAPS.EFF, just in a different format.