Exposure start time (Modified Julian Date). NOTE: This keyword is present for backward compatibility with ground system software. Where possible, use the FITS Standard keyword MJD-BEG for this quantity.
| Attribute | Value |
|---|---|
| data type | float |
| enumerated Values | not defined |
| units | days |
| example | 58827.74816625174 |
| default value | |
| special processing | VALUE_REQUIRED |
| source | Science Data Processing (SDP) |
| software source | |
| calculation | = input('DATE-OBS') + 'T' + input('TIME-OBS') / UTC exposure start time (MJD) |
| DB destination | ['ScienceCommon.expstart'] |
| data type in DB | float |
| instrument | Multiple |
| mode | All |
| product level | 1b |
| FITS hdu | PRIMARY |
| FITS header section | Exposure |