BIOMASS

BIOMASS (COSPAR 2025-090A, NORAD 63772) is an Earth-observing satellite developed by the European Space Agency and launched on April 28, 2025. Operated by the European Space Operations Centre, it represents one of ESA's most scientifically ambitious Earth Explorer missions, designed to deliver the first systematic, global-scale measurements of forest biomass from orbit. Weighing 1,250 kg at launch, the spacecraft is currently in a near-circular sun-synchronous orbit and continues to function in its operational phase.

Mission and Purpose

The central goal of BIOMASS is to close one of the most consequential gaps in Earth system science: a reliable, globally consistent accounting of how much carbon is stored in the world's forests. Forests are among the largest natural reservoirs of carbon on Earth, absorbing and holding vast quantities of carbon dioxide from the atmosphere. Yet the actual volume of woody matter—and therefore the carbon mass—contained in forest canopies and trunks has, until now, been extremely difficult to quantify at planetary scale using existing remote-sensing tools. Ground surveys are labor-intensive and geographically uneven, while many previous satellite instruments struggled to see through dense forest canopy layers to the full volume of biomass beneath.

BIOMASS addresses this limitation through the use of a P-band synthetic aperture radar (SAR), a long-wavelength radar system capable of penetrating forest canopies and returning information about the three-dimensional structure of tree trunks and large branches below. This long-wavelength approach allows the sensor to capture data from denser and taller forests that shorter-wavelength instruments cannot adequately characterize. The result, over the mission's planned five-year lifespan, is expected to be a time series of global forest biomass maps of unprecedented accuracy and coverage.

Beyond simply measuring how much carbon forests hold at a single moment, BIOMASS is designed to detect how those stores change over time. Deforestation, forest degradation, regrowth following disturbance, and the effects of drought and fire are all expected to leave detectable signatures in the mission's data archive. By monitoring at least eight seasonal or annual growth cycles across the world's forested regions, the mission aims to give scientists a dynamic picture of forest ecosystems rather than a static snapshot. This temporal depth is particularly important for understanding feedback loops between forest carbon stocks and the broader climate system.

The data produced by BIOMASS are intended to be freely available to researchers, policymakers, and organizations involved in carbon accounting and land-use monitoring. In practical terms, improved biomass measurements are relevant not only to climate science but also to international frameworks for tracking deforestation and forest degradation, where accurate baseline data are essential for credible reporting and verification.

Orbit and Tracking

BIOMASS occupies a sun-synchronous orbit (SSO), a category of near-polar orbit in which the satellite's orbital plane precesses at a rate that keeps it aligned with the Sun-Earth geometry throughout the year. This means the spacecraft passes over any given point on the Earth's surface at approximately the same local solar time on each revisit, ensuring consistent illumination and atmospheric conditions for the sensors—an important consideration for any Earth-observation mission requiring systematic, comparable data across seasons and years.

The orbit is very nearly circular: as of current catalog data, the apogee stands at 674 km and the perigee at 672 km, giving an altitude variation of only 2 km between the highest and lowest points of each orbit. This tight near-circularity is typical of precision Earth-observation missions, where a stable and predictable ground track is important for repeat-pass interferometry and long-term data consistency. The orbital inclination is 98.1°, which is the retrograde tilt characteristic of sun-synchronous orbits at this altitude range. The spacecraft completes one full orbit every 98.1 minutes, meaning it circles the Earth roughly 14 to 15 times per day.

These parameters allow BIOMASS to achieve systematic global coverage, revisiting the same geographic areas at regular intervals over the course of its mission. For a P-band SAR mission focused on forests, repeat-pass capability is not merely convenient—it is essential, since certain radar analysis techniques rely on comparing returns from the same location acquired at different times under nearly identical geometric conditions.

The spacecraft is tracked under NORAD catalog ID 63772 and international designator 2025-090A, and remains in orbit as of the time of this writing. Tracking data from ground-based radar networks and two-line element sets allow its current position to be computed in real time and are updated regularly in orbital databases.

Design and Operator

BIOMASS was built by Airbus Defence and Space, a major European defense and aerospace contractor with extensive experience in satellite manufacturing for both commercial and institutional customers. The spacecraft has a launch mass of 1,250 kg. The design centers on the P-band SAR antenna, which requires a large deployable reflector or array to function effectively at the long wavelengths involved—a significant engineering challenge that influenced the overall architecture of the spacecraft.

Day-to-day operational control of BIOMASS is handled by the European Space Operations Centre (ESOC), based in Darmstadt, Germany. ESOC serves as the primary flight operations hub for ESA missions, responsible for maintaining contact with the spacecraft via its global ground station network, monitoring spacecraft health, uploading commands, and managing the orbit. The European Space Agency, headquartered in Paris, retains ownership of the mission and oversees the scientific program, data policy, and long-term objectives.

BIOMASS is part of ESA's Earth Explorer program, a series of research-focused satellite missions each targeting a specific scientific question about the Earth system. Earth Explorer satellites are characterized by innovative instrument concepts often representing the first flight demonstration of a particular observation technique at global scale. BIOMASS fits firmly within this tradition: P-band SAR has not previously been operated in orbit for systematic forest monitoring from a dedicated civilian mission.

Significance

The scientific significance of BIOMASS extends beyond its immediate measurement objectives. Accurate knowledge of forest biomass and its rate of change is foundational to understanding the global carbon cycle—one of the most important and incompletely known components of the Earth system. Current estimates of how much carbon forests hold, and how quickly those stocks are changing, carry large uncertainties that propagate into projections of future atmospheric carbon dioxide concentrations and, by extension, into climate models. Better forest biomass data will tighten those estimates and potentially revise our understanding of how large a role forests can play as carbon sinks under different land-use and climate scenarios.

For national and international policymakers, BIOMASS data may support efforts to verify carbon stock changes in tropical and boreal forests, regions where on-the-ground measurement is logistically difficult and where independent verification of reported forest conditions has historically been limited. This has implications for carbon markets, emissions reporting, and international climate agreements that include forest-related commitments.

From a remote-sensing technology standpoint, BIOMASS marks the first time a civilian satellite has operated a P-band SAR in orbit for Earth observation purposes. Demonstrating the technology on orbit and building a pipeline from raw radar returns to validated, science-ready biomass products will establish methodologies and benchmarks that could inform future missions. The archive it generates over five years will itself become a scientific resource whose value increases over time, as longer time series allow detection of trends that are invisible in shorter records.

The mission also contributes to ESA's broader mandate of developing satellite-based services that address global environmental challenges. As forests come under increasing pressure from land conversion, climate-driven stress, and fire regimes altered by warming temperatures, an independent and systematic global monitoring capability takes on practical as well as scientific importance.

Current Status

BIOMASS launched on April 28, 2025, and as reflected in current orbital catalog data, the spacecraft remains in orbit. Because mission status is not confirmed in publicly available catalog records at this time, the specific phase of operations—whether the satellite is in commissioning, early orbit, or routine science operations—is not confirmed here. Initial phases following launch for Earth Explorer missions typically involve spacecraft checkout, instrument deployment verification, and calibration activities before systematic science data acquisition begins. Details of the mission's operational status and early results, as they become available, will be reflected in updates from ESA and ESOC.

Tracking enthusiasts and researchers can follow BIOMASS using its NORAD catalog ID 63772 or international designator 2025-090A in satellite tracking tools, including this site's own real-time position data. At an orbital altitude of approximately 673 km and with a period of 98.1 minutes, the spacecraft passes over most of Earth's populated latitudes multiple times daily, though its observational focus is on forested regions rather than urban areas.