15 September 2026 year Fr. 01:21 (UTC) from the Kura cosmodrome, French Guiana, "Sentinel-3C" and "FLEX" spacecraft were launched using the "Vega-C" launch vehicle.
"Sentinel-3C" is the third spacecraft of the Copernicus Sentinel-3 program, intended for comprehensive monitoring of land and oceans. It will measure the surface temperature of the sea and the land, the level and height of the ocean, the color of the ocean, sea ice thickness, state of vegetation, areas of forest fires, changes in ice sheets and the level of inland water bodies. The obtained data are used in oceanography, weather forecasting, environmental monitoring and climate change research. KA is close to the mass 1,2 t will work in an orbit with an altitude of about 815 km; estimated service life — 7 years.
"FLEX" is a scientific spacecraft of "ESA", the main task of which will be the study of plant fluorescence, which occurs during photosynthesis. Based on these data, scientists will be able to estimate the intensity of photosynthesis, state of vegetation and processes of carbon and water exchange between plants and the atmosphere. The satellite is equipped with the FLORIS instrument, which will register the weak fluorescent radiation of plants, which occurs during photosynthesis. These data will make it possible to assess the state of vegetation, its response to environmental changes and the role of plants in global carbon and water cycles.
"Vega-C" is a European light-class launch vehicle, developed by the Avio company under the program of the European Space Agency (THIS) for launching small and medium-sized satellites and other payloads into low Earth and sun-synchronous orbits.
The fourth degree of "Vega-C" is AVUM+ (Attitude Vernier Upper Module) — provides orientation control and accurate payload output to given orbits. Its main engine RD-843 was developed by Ukrainian specialists of the State Design Bureau "Southern" and the State Enterprise "Production Association "Southern Machine-Building Plant named after O. M. Makarov ".
RD-843 is a liquid rocket engine, which operates on unsymmetrical dimethylhydrazine (UDMH) and nitrogen tetroxides (N₂O₄). The engine provides multiple power-ups during a single mission, which enables AVUM+ to perform maneuvers and precisely form a target orbit.