Europe · ESA / European Union / Sensors & Defense

Sentinel-1C

Civilian Copernicus radar satellite illustrating the separate evidence for launch, calibrated products, constellation coverage and data-product delivery. A September notice records an ETAD processing delay; it is not a current whole-mission outage report.

DOCUMENTED STAGECalibrated data service; ETAD delay documentedEvidence through 4 Sept 2026Sources reviewed 4 Oct 2026

THE DEVELOPMENT RECORD

Milestones, with receipts.

5 Dec 2024

Launch completed

ESA reported that Sentinel-1C lifted off on Vega-C on 5 December. The linked release was published on 6 December; the timeline uses the stated launch date.

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10 Dec 2024

First radar images published

ESA released initial images while explicitly describing the satellite as still in commissioning. Images from an early mission do not by themselves establish calibrated routine service.

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29 Jan 2025

Preliminary samples opened to users

Copernicus made an initial Sentinel-1C sample dataset available with a quality disclaimer during commissioning.

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19 May 2025

Calibrated operational products begin

A Copernicus notice published on 21 May states that products processed from 19 May meet mission quality standards after commissioning. Earlier processed data retained a quality disclaimer.

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24 Jun 2026

New constellation configuration confirmed

Copernicus reported Sentinel-1C at its target orbital position and a restored nominal six-day interferometric repeat cycle with Sentinel-1D. This confirms completion, beyond the earlier planned transition dates.

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4 Sept 2026

Auxiliary-product delay reported

Copernicus reported delayed ETAD production for Sentinel-1C and 1D observations from 27 August onward. ETAD supplies timing corrections used with radar products. The notice said backlog recovery would follow; it did not announce completed recovery or a halt to all satellite observations.

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SUPPORTED BY THE RECORD

What we know

ESA documents completed launch, first images and the subsequent calibration process.
Copernicus distinguishes preliminary products from calibrated operational products.
The June notice confirms the new two-satellite repeat-cycle configuration.
A September notice documents a delay in one auxiliary product stream, distinct from the June constellation milestone.

STILL OPEN

What we don’t know

The reviewed record does not establish whether the September ETAD backlog has cleared or uninterrupted availability of every product stream.
A nominal repeat cycle does not promise an immediate image of every location or suitability for every analysis.
The selected sources do not independently validate every proposed downstream maritime or security application.

Scope of this record

Selected ESA and Copernicus evidence through 4 September 2026, reviewed 4 October 2026. The September notice concerns a specific auxiliary data product; this record does not establish whether its backlog has since cleared. Sentinel-1C is a civilian mission included for sensing and data-quality lessons. This is not a live satellite-health or availability feed.

SOURCE REGISTER

Read the evidence.

01
Double win for Europe: Sentinel-1C and Vega-C take to the skiesEuropean Space Agency · 6 Dec 2024
02
Sentinel-1C captures first radar imagesEuropean Space Agency · 10 Dec 2024
03
Release of preliminary Copernicus Sentinel-1C sample datasetESA / Copernicus Sentinel Online · 29 Jan 2025
04
Sentinel-1C products are now calibratedESA / Copernicus Sentinel Online · 21 May 2025
05
Sentinel-1C/1D Final Orbital Configuration AchievedESA / Copernicus Sentinel Online · 24 Jun 2026
06
Sentinel-1 Temporary delay in ETAD productionESA / Copernicus Sentinel Online · 4 Sept 2026
07
Sentinel-1 Extended Time Annotation Products (ETAD) now availableCopernicus Data Space Ecosystem · 12 Dec 2023