Biomass

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Biomass
Type: Earth observation satellite
Operator: European space agencyESA ESA
Mission dates
Dimensions: 1170 kg
Size: 10 × 12 × 20 m
Begin: 4th quarter 2022 Template: future / in 2 years(planned)
Starting place: CSG , ELV
Launcher: Vega C
Flight duration: 5 years (planned)
Status: in development
Orbit data
Apogee height :  672 km ( SSE )
Perigee height :  635 km (SSE)

Biomass is a planned Earth observation satellite of the European Space Agency (ESA). Starting in 2023, it will Template: future / in 2 yearsuse radar to measure the biomass of all of the world's forests and monitor their changes. The aim is to determine the carbon storage capacity of forests over time. Among other things, this should enable conclusions to be drawn about the connection between the global carbon cycle and climate change .

The mission is designed for at least five years. It is the seventh satellite in ESA's Earth Explorer program. All of these satellites are also used to test new technologies.

Mission objectives

The ESA specifies the following mission objectives:

  • Better understanding and quantifying the contribution of land areas to the global carbon cycle
  • Quantification of carbon flux due to changes in land use
  • much better modeling of the land-based carbon cycle
  • Rasterized, "high-resolution" estimation (200-meter raster) of the global aboveground biomass
  • Monitoring and quantification of forest disturbance and forest recovery
  • Monitoring and quantification of wetlands and forest flooding
  • Mapping of the structures below the surface of the earth in the polar regions
  • Mapping of the geomorphology below the earth's surface in arid zones

Planning and course

The Earth Explorer program proposed a total of 24 satellite missions up to 2006, including biomass . From 2009 to 2012 the feasibility of biomass and two other satellites was examined. In 2013, ESA chose biomass as the seventh mission in the Earth Explorer series. Two years later, the project was approved by the ESA member states, with a planned start time in 2020.

In 2016, the British branch of Airbus Defense and Space received an order worth € 229 million to build the satellite. The launch was now planned for 2021, but was postponed to 2022 at the earliest. The new Vega C is to be used as a launcher .

In the first year after the start, biomass is to measure the forest areas horizontally, with the earth being flown over in strips in a sun-synchronous orbit . From the second year onwards, the same strips should be flown over repeatedly at slightly different heights, which enables the vertical density of the forests to be measured using interferometric calculations.

Satellite technology

The core of the satellite is a synthetic aperture radar . It works in the P frequency band (at 435 ± 3 MHz ) and achieves a resolution of 0.25  hectares . The P-band is characterized by a particularly high sensitivity for the main components of forest biomass, i. H. for tree trunks and branches. In order to be able to use this radar frequency range (for the first time) from space, a new amplifier technology is to be used; conventional tube amplifiers would be too big and too heavy. For this purpose, ESA had new types of transistors made from gallium nitride semiconductors developed. They are more temperature-resistant than conventional components and should have a ten times higher output power in the required frequency range. The transistors are each designed for an output of 15 or 80 watts ; a three-part amplifier with a peak power of 3 × 120 watts is built.

For the radar antenna, a series product from the US communications and military technology manufacturer Harris Corporation was chosen . It can be folded up so that, despite its diameter of 12 meters, it fits into the payload compartment of the Vega rocket.

The measuring instrument should have a mass of around 200 kg, plus 75 kg for the antenna. It should consume a maximum of 463 watts of power and deliver a raw data rate (before compression) of 115 Mbit / s .

Ground stations

The biomass data are to be received by ESA's Kiruna ground station in Sweden and processed further in the European Space Research Institute in Italy. Mission control will be at the European Space Control Center (ESOC) in Darmstadt.

Similar missions

Interferometric radar measurement data, which were used to estimate the biomass, so far only exist from measurements in the higher-frequency L-band . They come from the Japanese Advanced Land Observing Satellite (ALOS, 2006–2011) and its successor ALOS 2 (since 2014).

Individual evidence

  1. ↑ a b Future missions - Biomass. ESA, accessed on December 7, 2018 (mass including 67 kg of fuel).
  2. ↑ a b c Biomass. In: ESA - Earth Online. Retrieved December 7, 2018 .
  3. ^ Arianespace and ESA announce the Earth Explorer Biomass launch contract. Arianespace, October 18, 2019, accessed October 18, 2019 .
  4. ↑ a b c Gunter Dirk Krebs: Biomass (Earth Explorer 7). In: Gunter's Space Page. December 11, 2017, accessed December 7, 2018 .
  5. ↑ a b c d e f g h i j k Biomass (Biomass monitoring mission for Carbon Assessment). In: eoPortal. ESA, accessed December 7, 2018 .
  6. ↑ Biomass monitoring mission for Carbon Assessment (BIOMASS). Center d'Etudes Spatiales de la Biosphére, accessed December 7, 2018 .
  7. ↑ Key components of tree-counting Biomass radar cleared for space. ESA, October 16, 2018, accessed December 7, 2018 .