| comment | str | The comment of the fits header item | |
| extension | int | The extension where this item occurs (0 for primary) | |
| fits | DataObject | The (fits file) object this header item belongs to | |
| name | str | The name of the fits header item | |
| position | int | The position of the item in the header | |
| value | str | The value of the fits header item | |
