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AORKEY = 12091136
PI = Kathleen Kraemer
PROGID = 3121
PROTITLE = Infrared Dark Clouds in the Inner Galaxy
OBJECT = DF18_cluster
PKUPACCU = Moderate
PKUPFILT = BLUE
PKUPFLUX = 133.500
PKUPXTND = 0
PTGDIFF (ACQ) = 0.076098393
PTGDIFF (SS) = 42.249523
ACQ XC = 11972
ACQ YC = 1025
SS XC = 10887
SS YC = 2799
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EXPLANATION
The sence is complex. A bright source at the edge of the field
was correctly centroided in ACQ, moved to the SS and then to the slit.
It's likely that the science target was lost, but observer should
double check.