Keyword indicates the moving target shadow state for the visit: SHADOW, SCIENCE, NONE (default). NONE indicates the visit is either not a moving target visit or a moving target visit without a paired shadow visit. SCIENCE indicates this is a moving target science visit linked to a moving target shadow visit. SHADOW indicates this visit is paired with another identical moving target SCIENCE visit with AFTER BY and SAME ORIENT link constraints. After the moving target SCIENCE visit has executed, this visit will be scheduled to use the same guide star and track the same path across the sky without the target in the field of view. The shadow observation can then be subtracted from the original SCIENCE observation to remove the background sources, leaving only the target behind. The target must be completely out of the field when the SHADOW observation occurs; the minimum time between SCIENCE and SHADOW observations is 10 days and the maximum separation is 53 days.
| Attribute | Value |
|---|---|
| data type | string |
| enumerated Values | ['SHADOW', 'SCIENCE', 'NONE'] |
| units | |
| example | SHADOW |
| default value | NONE |
| special processing | VALUE_REQUIRED |
| source | Proposal and Planning System (PPS) |
| software source | PPS:dms_observation_visit_view.moving_target_shadow |
| calculation | |
| DB destination | ['ScienceCommon.mtshadow'] |
| data type in DB | nvarchar(10) |
| instrument | ALL |
| mode | All |
| product level | 1b |
| FITS hdu | PRIMARY |
| FITS header section | Visit information |