OHB Contributing to ESA’s Earth Explorer Mission FLEX

OHB System AG was contracted to play a substantial role in the European Earth Explorer mission FLEX which is scheduled for launch in 2022. For the prime contractor Leonardo-Finmeccanica, OHB will design and develop important parts for the FLEX instrument.

On November 7th, 2016, Leonardo signed a EUR 74 million contract with the European Space Agency (ESA) to design, build and test the instrument for the satellite FLEX (FLuorescence EXplorer), ESA’s eighth Earth Explorer. OHB System AG was selected Leonardo’s primary partner and thus awarded a EUR 30 million contract by Leonardo. “Our contract covers one of the two spectrometers, both camera systems and the optical slit assembly for the FLEX instrument. We will ensure our full support to make the project go ahead straight forward”, said Dr. Ingo Engeln, Member of the OHB Management Board, after signing the contract. Leonardo will lead a consortium of several European companies over a four year period to create the FLEX instrument.

The Instrument

The FLEX spectrometer will, for the first time, allow observation of the photosynthetic activity of plants directly from space. The fluorescent effect occurring during photosynthesis will be used to study the health of Earth’s vegetation.

The optical instrument will be composed of a high-resolution and a low-resolution spectro-meter channel (with a spectral resolution of 0.1 or 2 nm, respectively). It operates in the spectral range of 500 nm to 780 nm, which means in the visible wavelength range to the near infrared. The ground resolution covers 300 m x 300 m so that diverse agricultural areas, including also timberland, can be sufficiently well distinguished.

The FLEX satellite will fly in tandem formation with Sentinel-3, another of ESA’s Earth observation satellites. Consequently, the data from two further instruments may also be factored into the evaluation, further increasing the informative value. It is planned for FLEX to monitor changes over three complete vegetation cycles.

OHB Responsibilities & Expertise

As primary partner of Leonardo-Finmeccanica, OHB System AG is responsible for major subsystems:

the camera systems including the detectors and front-end electronics for both spectrometers, that is one of the key parts of the instrument
the optical slit assembly defining the entrance apertures of the two spectrometers and separating the optical paths of the two spectrometers
the complete development and realization of the low-resolution spectrometer.

“We can make optimum use of our skills in system engineering, optical design, opto-mechanical design as well as our electro-optical expertise in the so called focal plane system“, says Stefan Föckersperger, Director Earth Observation, and adds: „We have acquired a lot of expertise, i.e. with the instruments for the sounder satellites and/or the telescope assemblies for the imaging satellites of the future European MTG weather satellites”.

OHB has established an excellent reputation over decades as a partner in science. “Optical systems belong to our solid core competencies”, explains Dr. Timo Stuffler, Director Business Development, “OHB covers everything in the development and construction of optical systems for the entire wavelength spectrum”.