ESA greenlights Hibidis and SOVA-S Scouts

The European Space Agency selected Hibidis and SOVA-S as its next two Scout missions on May 20, 2026, adding two small Earth-observation satellites to a program built around faster development and lower costs. ESA said the missions were chosen from four final concepts under its FutureEO program. Hibidis is aimed at measuring biodiversity beneath forest canopies, while SOVA-S will study atmospheric gravity waves in the upper atmosphere. ESA says Scout missions are meant to be delivered within three years from kick-off to launch and within a budget of €35 million. ### What exactly did ESA approve? ESA said Hibidis and SOVA-S were the two winners of its latest Scout selection round, after a competition among four candidate missions. The agency described the program as a complement to its larger Earth Explorer missions, using smaller satellites to test new observing techniques or miniaturized technologies. (esa.int) The four finalists were Hibidis, NAIAD, SIRIUS and SOVA-S, according to ESA material presented at the Living Planet Symposium. ESA said the candidates were studied in detail before the final down-selection to two missions for implementation. ### What will Hibidis actually measure? Hibidis is designed to study understorey biodiversity and ecosystem functioning below forest canopies, an area that is difficult to observe from space with conventional approaches, ESA said. (esa.int) ESA material describes the mission as a hyperspectral biodiversity scout intended to improve habitat mapping and refine classification of understorey species. (lps25.esa.int) The mission’s focus is on selected regions of interest rather than a broad generalized survey, according to the presentation material. ESA said the science case centers on local ecosystem structure, composition and function, including how ecosystems undergo critical transitions. ### What is SOVA-S meant to do in orbit? SOVA-S, short for Satellite Observation of Waves in the Atmosphere – Scout, will investigate how atmospheric gravity waves affect the upper atmosphere and thermosphere, ESA said. (esa.int) The satellite will carry a shortwave infrared imager to provide near-global daily observations of gravity waves at altitudes between 80 kilometers and 120 kilometers. (lps25.esa.int) ESA said SOVA-S will measure the intensity of “airglow,” the faint light produced by chemical reactions in the atmosphere. Those observations are intended to track wave activity high above Earth on a daily basis. ### How do these fit with HydroGNSS? HydroGNSS was ESA’s first Scout mission and launched on November 28, 2025, aboard a SpaceX Falcon 9 rideshare mission, ESA said. (esa.int) The two-satellite mission uses GNSS reflectometry to measure hydrological variables including soil moisture, wetlands and inundation, freeze-thaw dynamics and above-ground biomass. (esa.int) ESA says the Scout line is intended to add focused science missions alongside other Earth-observation satellites. In its description of HydroGNSS, the agency said the newer Scout candidates included Hibidis and SOVA-S, which have now moved from study phase to selection. ### What happens next for the two new Scouts? ESA said Scout missions are structured around rapid implementation, with a target of three years from kick-off to launch. (esa.int) The agency celebrated the Scout milestone at the Living Planet Symposium with the industrial leads tied to the candidate missions. The next formal step is implementation of Hibidis and SOVA-S as ESA’s newest Scout satellites. (esa.int) HydroGNSS is already in orbit, and ESA’s current Scout framework sets the benchmark for the two new missions at €35 million each and a three-year path to launch. (esa.int 1) (esa.int 2)