Spacecraft Z spatial coordinate, relative to the geocentric terrestrial reference frame, in meters, at the mid-point of the exposure, using the J2000 (ECI) coordinate system.
| Attribute | Value |
|---|---|
| data type | float |
| enumerated Values | not defined |
| units | meters |
| example | |
| default value | |
| special processing | VALUE_REQUIRED |
| source | Science Data Processing (SDP) |
| software source | |
| calculation | jwst_z value from either DefEphemeris or PredictEphemeris tables where useAfter date is closest to the exposure's EXPMID time, converted from km to m. |
| DB destination | ['ScienceCommonExt.obsgeo_z', 'GuideStarExt.obsgeo_z'] |
| data type in DB | float |
| instrument | ALL |
| mode | All |
| product level | 1b |
| FITS hdu | SCI |
| FITS header section | Ephemeris |