### Instruction:

Extract the cause and effect entities from the following sentence:
Otherwise (50% sky visibility) the observation time when the bulge is visible to LOFT is used for a significant fraction by observing the core-science targets

### Assistant:

KEYWORD: when
VARIABLE: the observation time
CONDITION: is used for a significant fraction by observing the core-science targets
CAUSE_1: the bulge is visible to LOFT
NOT_RELEVANT: (50% sky visibility)
EFFECT_1: is used for a significant fraction by observing the core-science targets
NEGATION: Otherwise

