- Testing to be undertaken in Munich – Launch from Baikonur in October
- Mapping of the Earth with innovative radar interferometer
- High-precision digital elevation model available as of 2012
During mid June, the satellite, which is five metres long and weighs 1.3 tonnes, has been transported to Ottobrunn near Munich where has been tested at Astrium’s and IABG’s test facilities. TamDEM-X remains there until mid-September, where final checks will be conducted ahead of launch. It will then be transported to the Baikonur space centre (Kazakhstan) with lift-off aboard a Russian Dnepr launcher scheduled for October.
TanDEM-X will fly in tandem formation with the identical TerraSAR-X satellite for a period of two years, generating a digital elevation model of the Earth’s land masses. By flying in close formation at distances of just a few kilometres to 200 metres apart, both satellites form a radar interferometer. Through this process the satellites will be able to provide radar images of unprecedented quality over the coming years.
As with the TerraSAR-X ’sister mission’, the TanDEM-X project was implemented in a Public-Private Partnership (PPP) between Astrium GmbH and DLR. The PPP agreement provides TanDEM-X funding and data utilisation. Thus, the partners (DLR and Astrium) jointly financed the satellite to the total of approximately €85 million: €59 million was provided by DLR and €26 million by Astrium. Furthermore, DLR has developed the mission-relevant ground segment and is responsible for mission planning and implementation, as well as for the control of both satellites and the generation of the digital elevation model. Data exploitation for scientific purposes is coordinated by the DLR institute for high-frequency technology and radar systems. Infoterra GmbH (Friedrichshafen), a wholly owned subsidiary of Astrium, is exclusively responsible for commercial marketing.
With the aid of the tandem formation of TerraSAR-X/TanDEM-X it will be possible to completely measure the Earth’s land surface (150 million square kilometres) within a period of only three years. For a 12-metre grid (street width), height information can be determined with an accuracy of less than two metres.
The distinct advantage of satellite-based Earth measurement is the generation of a world-wide, consistent and homogeneous terrain model with no discontinuity at regional or national borders and no inhomogeneities resulting from different measurement procedures and measurement campaigns staggered in time (mosaics). The radar plays a decisive role here, since it can be operated completely independent of weather and clouds, day and night.
This mapping procedure is unparalleled and is of particular interest to the USA. TanDEM-X is a key project for demonstrating, safeguarding and extending the German competence and competitiveness in the field of satellite-based radar technology.
As of 2012, Germany will possess a digital terrain model of the Earth – an attractive and worldwide unique data product – which, in addition to many scientific application possibilities, can be used in initiatives and programmes, such as the centre for satellite-based crisis information (ZKI – Zentrum für satellitengestützte Kriseninformation), GMES (Global Monitoring for Environment and Security) and GEOSS (Global Earth Observation System of Systems), and also in security-relevant cooperation agreements.
The TanDEM-X project is being implemented by a Public-Private Partnership (PPP) between the German Aerospace Center (DLR) and Astrium GmbH.
The primary goal of the TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement) mission is to generate a global digital elevation model. To achieve this, two satellites – TanDEM-X and TerraSAR-X, a satellite of almost identical construction which has been in orbit since 2007 – will form the first configurable SAR (Synthetic Aperture Radar) interferometer in space with a separation of only a few hundred metres. A powerful ground segment which is closely interfaced with that of TerraSAR-X completes the TanDEM-X system. The satellites will fly in formation and operate in parallel for three years to cover the entire surface of the Earth.
DLR is responsible for the scientific exploitation of the TanDEM-X data as well as for planning and implementing the mission, controlling the two satellites and generating the digital elevation model. Astrium built the satellite and shares in the cost of its development and exploitation. As with TerraSAR-X, the responsibility for marketing the TanDEM-X data commercially lies in the hands of Infoterra GmbH, a subsidiary of Astrium.