| CatalogCoverage | SpatialFootprint | CatalogCoverage | |
| DataStorage | ExtSourceCatalogFitsFile | Storage container for the single detector image | |
| Detector | str | Information about the detector chip [None] | |
| Filter | BaseFilter | Information about the observational filter [None] | |
| Instrument | GroundInstrument | Information about the acquisition instrument [None] | |
| ObservationDateTime | GroundObservationDateTime | Date and time of the acqusition of the data stored in this frame. By convention this is the UTC date at the start of the observation. Analog to FITS DATE-OBS keyword. | |
| ProcessParams | ExtSourceCatalogParameters | Processing and verification parameters [None] | |
| QualityParams | ExtSourceCatalogDqp | QualityParams | |
| TileIndex | int | MER tile index | |
