A timestamp for exposure start, including fraction of day; equivalent to keyword EXPSTART (Modified Julian Date).
| Attribute | Value |
|---|---|
| data type | float |
| enumerated Values | not defined |
| units | days |
| example | 58058.23456789 |
| default value | |
| special processing | VALUE_REQUIRED |
| source | Science Data Processing (SDP) |
| software source | |
| calculation | identical to EXPSTART |
| DB destination | ['ScienceCommonExt.mjd_beg'] |
| data type in DB | float |
| instrument | Multiple |
| mode | All |
| product level | 1b |
| FITS hdu | SCI |
| FITS header section |