# Sentinel-1D
*missions*

## Specifications
- **operator**: esa
- **actual launch**: "2025-11-04T00:00:00.000Z"
- **current status**: operational
- **orbit type**: Sun-synchronous, 693 km, polar, 18:00 LTDN (constellation design)
- **swath km**: 250
- **revisit days**: 12
- **tasking supported**: 0
- **archive depth years**: 1
- **last verified date**: 2026-05-24
- **verified by**: agency-doc
- **claim status**: agency-sourced
- **paired revisit days**: 6

## Editorial
Sentinel-1D is a C-band synthetic aperture radar (SAR) satellite developed and operated by ESA as part of the Copernicus Earth observation programme, on behalf of the European Commission.[^esa-main] Airbus Defence and Space served as prime contractor. Sentinel-1D was launched 2025-11-04 on an Ariane 6 rocket (Arianespace flight VA265) and completed in-orbit commissioning on 2026-05-01.[^esa-s1d-goes-live] [^arianespace-va265] User data access opened on 2026-04-17.[^copernicus-data-opening]

Sentinel-1D carries a C-SAR instrument operating at 5.405 GHz (C-band) plus an Automatic Identification System (AIS) receiver. Four imaging modes are available:[^esa-instrument]

| Mode | Swath | Resolution |
|---|---|---|
| Interferometric Wide Swath (IW) | 250 km | 5x20 m |
| Extra Wide Swath (EW) | 400 km | 20x40 m |
| Stripmap (SM) | 80 km | 5x5 m |
| Wave (WV) | 20x20 km vignettes at 100 km intervals | 5x5 m |

Sentinel-1D orbits at 693 km in a Sun-synchronous polar configuration with an 18:00 local time descending node.[^esa-facts] It is the fourth satellite in the Sentinel-1 series. The pairing of Sentinel-1C and Sentinel-1D gives a six-day revisit cycle with a one-day ground-track offset between the two satellites. Three-satellite operations with 1A, 1C, and 1D ran from mid-April to approximately mid-June 2026; the final operational pair is 1C and 1D, with Sentinel-1A scheduled for phase-out circa July 2026.[^copernicus-future-plans] Sentinel-1B ended operations in August 2022.

Sentinel-1D and Sentinel-1C both carry a new separation mechanism to reduce space debris risk, a design change relative to Sentinel-1A and 1B.[^esa-facts] Tasking is not supported; Sentinel-1D operates as an open-access, observation-mode instrument.

## Compositional position
- Sentinel-1D --[mission_payloads]--> c-sar (products)

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Source: https://eo-atlas.org/missions/sentinel-1d
Maintainer: SpectraWorks B.V. (CC-BY 4.0)