Skip to content

Interview with Susanne Mecklenburg and Achim Hahne to talk about some aspects relevant for the SMOS Mission

In this issue of EOMAG, EARSC will have the opportunity to feature an interview with Susanne Mecklenburg and Achim Hahne to talk about some aspects relevant for the SMOS Mission.


Please tell us something generic about your role as mission manager and the responsabilities for throughout the process of designing, building and the future launching SMOS

Susanne Mecklenburg: Since I became the SMOS Mission Manager in June 2007 I am responsible for all aspects of the mission in the operations phase. This means I will take care of the smooth running of the mission after launch in autumn 2009 and the subsequent commissioning phase and, most importantly, of the scientific exploitation of the data. We are now in the final stages of the development phase, which is led by my colleague Achim Hahne at ESA-ESTEC. He has been taking care of building the mission over the last years since SMOS was selected as the second Earth Explorer Opportunity Mission in 1999.

At the moment I am busy planning the operations phase, which comprises all scientific, technical and financial aspects of the mission. We now have all the ESA internal and industrial teams in place that will support the SMOS operations. The main activities at the moment focus on preparing for the SMOS commissioning phase, which will last 6 months after launch. This time will be dedicated to the calibration and validation activities, which are a major undertaking in any environmental science related satellite mission. Once the data get to the ground they need to be checked in terms of whether they make sense and can be used for scientific research.


How did the SMOS mission come about and what was involved in formulating the concept for the SMOS mission?

Achim Hahne: Formally speaking, the starting point for the SMOS mission was the proposal submitted by Y. Kerr and J. Font as Principle Investigators to ESA’s first Call for Proposals in the first slice of the Earth Observation Envelope Programme.

However, the work on the proposal was preceded by about 8-10 years of scientific investigations and technology development, which laid the foundation for the credibility of the proposed mission. The technology development covered not only the instrument principle and the receiver technology but also mission-critical elements like an overall calibration methodology, the principle of the structure and deployment mechanism, and the optical fiber harness for fast and radio- emission free data transmission.

During the definition phase, how difficult was it to balance the scientific requirements with what is feasible from an engineering perspective?

Achim Hahne: In spite of all this preparatory work there were moments in the early definition phase in which painful decisions had to be made: deletion of the additional C-band array, reduction of the numbers of receivers on the arm segments and in the hub. This could only be achieved in close cooperation with the involved scientists, by tuning other mission parameters or through ingestion of external data e.g. from ECMWF. Without these drastic measures, the mission would probably not have been feasible within the financial and programmatic boundaries (e.g. use of a recurrent PROTEUS satellite bus).

SMOS waiting for launch, Thales Alenia Space in Cannes in April 2009 ©ESA


How many people work on the project?

Achim Hahne: In the beginning, the main effort was concentrating on the payload development and delivery. With a small but experienced ESA project team, an excellent team spirit grew quite quickly between the ESA project team, the scientists, and the involved industry lead by EADS CASA (Spain). At the peak of the payload activities, just a little less than 100 people were working on SMOS issues in agencies, academia, and industry.

Please tell us about challenges SMOS have presented so far?

Achim Hahne: With the delivery of the payload to Thales Alenia Space (France), emphasis shifted from the development of novel technologies to an orderly environmental and functional test programme at satellite and system level. This put the French partner agency CNES into the foreground, as they hold the contracts for the satellite AIT programme and will operate, eventually, the satellite from the generic PROTEUS Satellite Operations Ground Segment.

Of course, different agencies not only have different internal rules and regulations but also different cultures, which have to be recognised and accepted.

Which partners are involved and how does the SMOS team work?

Susanne Mecklenburg: The SMOS mission is special in that three different agencies were involved and supported the development of the mission. In addition to the ESA funding there were significant national contributions provided by the French and Spanish space agencies, CNES and CDTI. This collaborative approach will partly continue in the operations phase, where ESA will be responsible for the overall coordination of the mission and the ground segment operations, whereas CNES will be operating the spacecraft. There is a significant number of ESA and CNES staff and industrial teams involved in the operations being located at different stations covering a variety of functionalities. The main stations to keep SMOS running day-to-day will be at ESAC Villafranca hosting the main part of the Data Processing Ground Segment and at CNES in Toulouse hosting the Satellite Operations Ground Segment, with their respective receiving stations. In addition we will operate another X-Band receiving station at Svalbard guaranteeing a near-real time data delivery to a few operational agencies such as ECMWF and MétéoFrance.

Other SMOS related stations are at Kiruna, where the reprocessing and archiving of the data will be done, at ESA-ESRIN in Frascati, which will host the mission management and the user services, and at ESA-ESTEC in Noordwijk, where the Post Launch Support Office will be located. This team will be responsible for the maintenance of the satellite and payload performances and will intervene in case of anomalies, reacting quickly to rectify non-nominal performances of the mission.

In addition to the teams that keep the mission running on a day-to-day basis we will have so called Expert Support Laboratories, consisting of industrial and scientific groups, supporting the calibration of the SMOS MIRAS data and the development of the retrieval algorithms to derive SMOS level 2 data for soil moisture and sea surface salinity. These consortia are strongly linked and scientifically led by the SMOS Principal Investigator Yann Kerr from Centre d’Etudes Spatiales de la Biosphère (CESBIO, Toulouse) and the Co-Principle Investigator Jordi Font from Institut de Ciències del Mar (ICM, Barcelona). In addition, there will be strong national efforts to develop level 3 (global, single-instrument) and 4 (global, multi-instrument) SMOS data products through the French Centre Aval de Traitement des Donnees SMOS (CATDS) and the Spanish SMOS Level 3/4 Processing Centre (CP34).

SMOS ground segment: the various functionalities will be covered by ESA and industrial teams ©ESA


Who will be the main users and how will SMOS data be delivered to users?

Susanne Mecklenburg: There are two main groups of users. Scientists, such as oceanographers, hydrologists, atmospheric physicists etc., will use the global measurements for their research projects. We already have a significant number of registered users who will receive data directly from the Data Processing Ground Segment at Villafranca or from the archive in Kiruna.

The other group of users, including the ECMWF and national meteorological services, will focus more on operational applications. They have requested to receive SMOS measurements within three hours of acquisition to assimilate the data into their forecasting models. ESA has responded to this need by establishing a near-real time service by funding a further ground station at Svalbard that will receive SMOS data more frequently than the ESAC station at Villafranca. ECMWF and MétéoFrance in particular are already now working on integrating these data in their predictive models, testing the improvements SMOS data will be able to make to meteorological forecasts.

What information can SMOS provide to potential users and what benefits will SMOS bring?

Susanne Mecklenburg: The original proposal for the SMOS mission was submitted more than 10 years ago with the main motivation to address the lack of global measurements of soil moisture and ocean salinity. These are two very important variables in the Earth’s water cycle and climate system, yet there are currently no global observations available. Furthering our knowledge about soil moisture, especially in the root zone, will improve short- and medium-term meteorological modelling, hydrological modelling, the monitoring of plant growth and the forecasting of hazardous events, such as floods. Global observations of ocean salinity will support the monitoring and modelling of the ocean circulation, which plays a crucial part in the climate system. In addition, SMOS will also improve the characterisation of ice and snow covered surfaces. Thus, the SMOS observations will be really innovative and make a significant change to many areas of research and applications. However, as with all Earth Explorer missions, these are really novel concepts and data and we will have to invest effort and time to exploit them to the full.

How will you compare SMOS products with others?

Susanne Mecklenburg: There will also be other soil moisture and ocean salinity observations provided by two satellite missions from NASA, Aquarius and Soil Moisture Active Passive (SMAP), which will be launched over the next years. Both will measure in the same spectral region, L-Band, as SMOS, but will also have different features that will make them complementary to the SMOS data. We are working closely with these two teams and hope to combine the data in future.


How important is it involving the EO service providers with the development of a mission such as SMOS?

Susanne Mecklenburg: For the operations phase we already have strong support from the EO service industry in place for all aspects of running the mission on a day-to-day basis. The support ranges from the acquisition, processing, quality control, distribution and archiving of the data to the maintenance and evolution of the systems we use. We are presently finishing the development of all the systems and services of the SMOS ground segment, working closely also with CNES. Final tests are underway and we are confident to have a robust and reliable system in place at the time of launch.


What role does the Prime Contractor play?

Achim Hahne: The specific programmatic setup with ESA and CNES cooperating for the space segment had one major implication for the industrial construction: the absence of an overall prime contractor! Whilst the payload was developed by EADS CASA under ESA contract, the provision of the PROTEUS platform and the merging of the platform and payload was done by Thales Alenia Space under CNES contract. Hence, the two cooperating agencies had to jointly assume the role of a prime contractor. This made the development particularly challenging but also rewarding.

What challenges has SMOS in terms of design? Will advancements made here also benefit future space missions?

With the excellent results obtained with the MIRAS instrument during ground testing, the concept of interferometry at microwave frequencies is now gaining momentum. Technology preparations for an operational SMOS – follow on have started, and concept studies for interferometric observations from the geostationary orbit are under way.

Industrial teams involved in developing the SMOS mission ©ESA


At the end of the interview, here is the opportunity for your final thoughts on the future, what do you see as the task ahead and would you like to give some message to the industry interested in SMOS products?

Susanne Mecklenburg: Of course we are always interested to have new users for SMOS data on board. ESA’s data policy foresees to make Earth Observation data as widely and freely available as possible. Therefore all data will be made available through the ESA category-1 procedure, either through dedicated Announcements of Opportunities or, for users who have not participated in the past AOs, registration service online EOPI. If you are interested in further information you can also consult the ESA Bulletin special issue on SMOS

More information at ESA Website

Thank you for your time, and for sharing your thoughts and comments with the EOmag readers

Eomag! 18_ Interview with Susanne Mecklenburg and Achim Hahne to talk about some aspects relevant for the SMOS Mission.pdf