ESA greenlights Hibidis, SOVA-S Scout missions

The European Space Agency said on May 20 that it had selected two new Earth-observing Scout missions, Hibidis and SOVA-S, expanding a small-satellite program built around faster, lower-cost science missions. ESA said its Earth Observation Programme Board formally approved the pair after a 10-month evaluation. The two missions were chosen from four finalist concepts that ESA had advanced in June 2025. ESA said Hibidis will study biodiversity below forest canopies, while SOVA-S will examine atmospheric gravity waves in the upper atmosphere and thermosphere. ### Which two missions did ESA approve? ESA said Hibidis and SOVA-S were selected for implementation from a field of four finalists. The agency described Hibidis as a “Hyperspectral Biodiversity Scout” mission and SOVA-S as “Satellite Observation of Waves in the Atmosphere – Scout.” The June 26, 2025 shortlist also included NAIAD, focused on coastal and inland aquatic ecosystems, and SIRIUS, aimed at urban heat islands and heat-related health risks. (esa.int) ESA said HIBIDIS was led by Sitael in Italy and SOVA-S by OHB in Czechia during the candidate phase. ### What will Hibidis actually measure? ESA said Hibidis is designed to improve understanding of understorey ecosystem biodiversity. (esa.int) The agency’s mission description says the satellite will carry a hyperspectral imager, and its approval notice says it is intended to reveal new insights into understorey biodiversity and ecosystem functioning. (esa.int) ESA’s earlier candidate announcement said the mission would study understorey biodiversity and ecosystem functions. A Sitael statement from July 2025 said HiBiDIS had been selected to explore hyperspectral imaging for biodiversity monitoring, consistent with ESA’s description of the mission. ### What is SOVA-S supposed to do in orbit? (esa.int) ESA said SOVA-S will investigate how atmospheric gravity waves influence the upper atmosphere and thermosphere. In a separate mission note, ESA said the satellite will carry a shortwave infrared imager and provide near-global daily observations of gravity waves at altitudes between 80 km and 120 km by measuring atmospheric “airglow.” (esa.int) DLR, which described the mission during its candidate phase in July 2025, said atmospheric gravity waves are not adequately represented in existing climate models even though they play a significant role in the atmosphere’s energy balance. DLR said SOVA-S was expected to gather data from a solar-synchronous orbit and that the candidate mission had been required to fit within ESA’s Scout cost ceiling. (esa.int) ### How does the Scout program work? ESA said Scout missions are part of its Earth Observation FutureEO program and are meant to complement the larger Earth Explorer line. The agency says Scout satellites are intended to deliver “value-added science” either by miniaturizing existing technologies or by demonstrating new observing techniques, with an emphasis on speed and low cost. (dlr.de) ESA said in its June 2025 candidate announcement that each Scout mission must be delivered within three years from kick-off to launch and within a budget of €35 million. That same notice said nine proposals had been evaluated before four were chosen for detailed study over nine months. ### Where do HydroGNSS, NanoMagSat and Tango fit in? (esa.int) ESA’s Scout program page says HydroGNSS, NanoMagSat and Tango were already in development before the latest selection. ESA describes the Scout line as a relatively recent component of FutureEO. The UK Space Agency said HydroGNSS, the first ESA Scout mission, launched on Nov. 28, 2025 aboard a SpaceX rocket and is designed to monitor the planet’s water cycle. (esa.int) ESA has previously linked NanoMagSat to magnetic-field science and Tango to greenhouse-gas observations in its Scout program materials. ### What happens next? ESA said only that Hibidis and SOVA-S had been formally approved by the Earth Observation Programme Board on May 20. (esa.int) The agency has not, in the approval notice, published launch dates for the two new missions. ESA’s published Scout framework says implementation follows selection, and its existing program page remains the main public tracker for mission status alongside mission-specific pages for Hibidis and SOVA-S. (gov.uk) (esa.int 1) (esa.int 2)