DR13

Other photometric observations (detections)

Due to overlaps in imaging stripes, the SDSS sometimes observes the same object more than once. In such cases, we select one observation as PRIMARY (mode=1). Each astronomical object is assigned a thingID, and each time that "thing" is observed (detected in SDSS imaging), it assigned a separate objID.

Information about each astronomical "thing" is stored in the thingIndex table; thingIndex is a thin coupling table designed only to connect repeat observations. Information about each individual observation (detection) is in the photoObjAll table. (Note that photoObj contains only the primary [mode=1] and secondary [mode=2] observations of each "thing.") The detectionIndex table connects each objID to the thingID it corresponds with.

This detected object and its associated "Thing" (Primary observation)

IAU nameobjidthingidmode description
SDSS J052157.33+005254.41237658188923602575116517185PRIMARY

Other Observations of this "Thing"

objidthingidmodemode description
12376581889236025751165171851PRIMARY
12376466483749208091165171852SECONDARY
12376467938380367841165171852SECONDARY