obsid   target                  start time      int time    inst    ccd     grat    drop rate(%)
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10642	Cas_A[I3,-120,-     	130:48275.925		 2.8	ACIS-I	I4		NONE	3.1
10643	Cas_A[S3,-120,-     	130:52497.441		 2.1	ACIS-S	S4		NONE	12.7