Sentinel-3C is an Earth-observation satellite developed by the European Space Agency (ESA) as part of the Copernicus Programme, the European Union’s flagship initiative for environmental and climate monitoring. It belongs to the Sentinel-3 mission family, which focuses on observing Earth’s oceans and land to support long-term climate records and operational environmental services.

The Sentinel-3 mission is designed to measure sea surface temperature, sea level, ocean color, and land surface temperature with high accuracy. These observations are essential for monitoring ocean health, tracking climate change, improving weather and ocean forecasting, and supporting marine and land-based environmental management.

Sentinel-3C is a near-identical successor to earlier Sentinel-3 satellites, ensuring continuity of measurements while improving overall coverage and revisit frequency. By flying alongside other Sentinel-3 spacecraft, it helps prevent data gaps and maintains the consistency required for long-term climate studies.

Data from Sentinel-3C is freely available worldwide and is used by scientists, meteorological agencies, and policymakers for applications ranging from marine navigation and fisheries management to climate research and disaster response. Its launch reinforces Copernicus as one of the most comprehensive and reliable Earth-observation systems currently in operation.

Photo courtesy of ESA.

FLEX (FLuorescence EXplorer) is an Earth-observation satellite developed by the European Space Agency (ESA) as part of its Earth Explorer program. The mission is dedicated to studying vegetation health and photosynthetic activity, providing new insight into how plants respond to environmental stress and climate change.

FLEX is the first satellite specifically designed to measure chlorophyll fluorescence from space, a faint light emitted by plants during photosynthesis. By observing this signal, FLEX can directly assess how efficiently vegetation is converting sunlight into energy, offering a powerful indicator of plant health, crop productivity, and ecosystem function.

The satellite carries the FLORIS (Fluorescence Imaging Spectrometer) instrument and is designed to fly in tandem formation with Sentinel-3C. This coordinated flight allows FLEX’s fluorescence measurements to be combined with Sentinel-3’s ocean, land, and thermal data, significantly enhancing scientific understanding of land–atmosphere interactions.

Data from FLEX will support climate science, agriculture, forestry, and carbon-cycle research, helping scientists better understand how Earth’s vegetation absorbs carbon dioxide and responds to changing environmental conditions. Its mission represents a major step forward in monitoring the biological processes that regulate the planet’s climate.

Photo courtesy of ESA.

ESA’s Vega-C is a next-generation launch vehicle that succeeds the original Vega rocket, offering enhanced performance, greater payload volume, and increased competitiveness. Operating from Europe’s Spaceport in French Guiana, Vega-C strengthens Europe’s independent access to space and supports a wider range of missions, including return-to-Earth operations with ESA's upcoming reusable Space Rider vehicle.

Specs

Height: 34.8 m (114 ft)

Diameter: 3.4 m (11 ft)

Mass: 210,000 kg (460,000 lb)

Stages: 4

Payload to sun-synchronous orbit: 2,300 kg (5,100 lb)

Payload to polar orbit: 2,250 kg (4,960 lb)

Vega-C is designed to accommodate a variety of missions, from launching small CubeSats to carrying a single large satellite. It features significant upgrades over its predecessor, including new solid propulsion stages, an enhanced upper stage with reignition capability, a larger fairing for increased volume, and upgraded ground infrastructure.

Its upper stage, AVUM+ (Attitude Vernier Upper Module), enables precise orbital insertions and multiple burns, making it ideal for delivering multiple payloads to different orbits in a single mission. Once all payloads are deployed, AVUM+ performs a final deorbit burn to minimize space debris.

Vega-C’s development and operations are supported by multiple ESA member states, reflecting broad European cooperation. Participating countries include Austria, Belgium, Czech Republic, France, Germany, Ireland, Italy, Netherlands, Norway, Romania, Spain, Sweden, and Switzerland.

Courtesy of ESA

The Ensemble de Lancement Vega (ELV) pad at the Centre Spatial Guyanais (Guiana Space Centre) was previously used to launch the Europa, Ariane 1, Ariane 2, and Ariane 3 rockets under a different name.

It hosted its first launch on November 5, 1971, when a Europa rocket carried the STV-4 payload. The pad was last used in 1989 for the final Ariane 3 launch before going unused until 2012, when Vega began operations.

Located in French Guiana, the ELV pad is part of the French and European spaceport near Kourou, on the northern coast of South America.

Guiana Space Centre

The Guiana Space Centre has been operational since 1968, serving the European Space Agency (ESA), the French National Centre for Space Studies (CNES), and commercial companies such as Arianespace and Azercosmos.

A total of nine different rocket types have launched from the spaceport, including three active rockets and six retired vehicles.

The current launch vehicles operating from the Guiana Space Centre include:

Ariane 5 – for heavy payloads.

Soyuz 2 (provided by Russia) – for medium-mass satellites.

Vega – for smaller spacecraft.

The spaceport is also preparing for the upcoming Ariane 6, Vega C, and Vega E rockets, which are currently under development.

Photo courtesy of Arianespace