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The European Space Agency, known as ESA, has chosen two new missions to study our planet. These missions, called Hibidis and SOVA-S, will help scientists answer important questions about Earth’s environment. The selection was made by the ESA’s Earth Observation Programme Board after a careful ten-month review process. Both missions are designed to be fast and affordable, representing a new approach to space exploration.
The first mission, Hibidis, stands for Hyper-spectral Biodiversity Scout. Its main goal is to check the health of ecosystems and biodiversity. It will focus on the forests and jungles covering much of the Earth’s surface. To do this, Hibidis will analyze the light spectrum coming from the understory, which is the layer of plants growing under the main tree canopy. The satellite will look at these areas from multiple angles to get a complete picture. Italy’s company SITAEL is the main builder of Hibidis. They are working with several partners, including Amos and Vito in Belgium and the University of Zurich in Switzerland. The satellite will sit on SITAEL’s new Empyreum small satellite platform. It will also use SPARK, an electric propulsion unit that is designed to be low-cost.
The second mission is called SOVA-S. This name stands for Satellite Observation of Waves in the Atmosphere. SOVA-S will use a special camera that sees in shortwave infrared light. This camera will regularly watch for gravity waves in the Earth’s atmosphere. These waves are not the same as gravitational waves, which are ripples in space-time caused by merging black holes or pulsars. Atmospheric gravity waves are physical movements of air. They look like moving rows or ripples in the sky. These waves are very powerful because they carry huge amounts of energy from the lower atmosphere up to higher altitudes. By tracking these waves, SOVA-S hopes to improve weather forecasts and help scientists understand how the atmosphere works.
Both Hibidis and SOVA-S are part of a category called Scout-class missions. These missions belong to the ESA’s Earth Observation FutureEO program. This program is a smaller, faster branch of the larger Earth Explorer program. Scout missions are built to solve specific scientific questions quickly and cheaply. There are strict rules for these projects. They must be ready for launch within three years of being selected. They also have a budget limit of 35 million Euros. This budget cap forces teams to be creative and efficient.
Simonetta Cheli, who directs the ESA’s Earth Observation Program, praised this new approach. She noted that groundbreaking science does not always require huge budgets or long development times. According to Cheli, moving fast and embracing innovation allows scientists to achieve more in less time. These missions show how agility and creativity can accelerate progress. They deliver important scientific data and new technology in a remarkably short time frame.
These two selected missions were not the only options. Two other projects were considered for selection. One was called SIRIUS, which stands for Space-Based Infra-red Imager for Urban Sustainability. The other was NAIAD, which stands for Near-coastal And Inland Aquatic Impact Data. Both of these projects aimed to study human impacts on the environment. However, the ESA board decided that Hibidis and SOVA-S were better suited for the current Scout-class goals.
Hibidis and SOVA-S join a growing group of Scout-class missions already in space or in development. The first Scout mission was HydroGNSS. It launched on November 28, 2023. It rode on a Falcon 9 rocket as part of the Transporter-15 rideshare mission. Rideshare missions allow small satellites to share a launch with other payloads to save money. Because Hibidis and SOVA-S are small satellites, they will likely use a similar rideshare launch in the future. They are expected to launch from Vandenberg Space Force Base in California. This launch will place them into a sun-synchronous orbit.
Other Scout missions are also being developed. One mission is called NanoMagSat. It will study how space weather affects the Earth’s local environment. Another mission is called Tango. Tango will monitor emissions from industrial facilities. These missions, along with Hibidis and SOVA-S, demonstrate the variety of scientific questions that can be answered with small, efficient satellites.
Sun-synchronous orbit, often called SSO, is a specific type of path that these satellites will follow. It is a high-inclination polar orbit. This means the satellite passes over the North and South Poles. It is a popular choice for surveillance and Earth-observing satellites. This orbit allows the satellite to cover the entire planet from pole to pole. It also offers consistent lighting conditions because the satellite passes over the same spot at the same local solar time. This consistency is very useful for comparing images taken at different times.
Launching into this orbit requires special planning. Satellites in sun-synchronous orbits must launch westward. This direction is against the rotation of the Earth. Launching westward helps the satellite reach its desired orbital speed and angle more efficiently. Because of this requirement, Vandenberg Space Force Base in California has become an increasingly popular launch site. Most launch sites on the East Coast launch eastward to take advantage of the Earth’s rotation for extra speed. Vandenberg is located on the West Coast, allowing for westward launches over the ocean.
The selection of Hibidis and SOVA-S marks a significant step for the ESA. It shows a commitment to developing agile, cost-effective tools for Earth observation. By focusing on specific scientific questions, these missions can provide detailed data without the complexity of larger projects. The use of small satellites and rideshare launches reduces costs and speeds up the timeline. This approach allows scientists to test new technologies and answer new questions more quickly than before. As technology improves, the Scout program is expected to grow. More missions like HydroGNSS, NanoMagSat, Tango, Hibidis, and SOVA-S will join the fleet. Together, they will provide a comprehensive view of our changing planet. This strategy proves that space science can be both rapid and rigorous. The insights gained from these missions will help us better understand and protect Earth’s delicate environments.