On 21 June 2010 the German Aerospace Centre (DLR) successfully launched its Earth observation satellite, TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement), from the Baikonur Cosmodrome in Kazakhstan. Its mission is to provide a homogeneous 3D elevation model of the Earth, said DLR Chairman Prof. Dr Johann-Dietrich Wörner.

The satellite built by the German private company Astrium GmbH includes a conventional active-radar sensor known in the space jargon as SAR; it weights over 1.3 tons and is 5 metres long.

Once operational and in orbit, TanDEM-X will fly in parallel, or in ‘tandem’, to its twin satellite TERRASAR X, which is in space since 2007, accomplishing a two 'radar eyes' design configuration, to survey the entire land surface area of the Earth - a total of 150 million square kilometres - several times over. This will allow for the creation, for the first time ever, of a globally standardised three-dimensional digital elevation model of Earth with a 12 metre resolution and a vertical accuracy of 2 metres.

DLR is one of the partners of the UNESCO-ESA ‘Open Initiative on the Use of Space Technologies to Support the World Heritage Convention’ and has been supporting UNESCO, among other projects, in its work on monitoring landslides in Machu Picchu. Within the project, space partners have been able to detect a certain irregular behaviour of the radar sensor. Due to its location in a highly mountainous area with an extremely accidental relief, the site’s observation has large areas ‘under severe shadow of the mountains’ that produces large ‘blind points’ for radar sensors. This makes the acquisition of data for certain areas impossible. The new DLR satellite TanDEM-X combined with TERRASAR-X are expected to be able solve these technical problems and thus provide to UNESCO the first complete images on Machu Picchu.

Related articles:

http://www.dlr.de/eo/en/desktopdefault.aspx/tabid-5727/10086_read-21046/

http://www.astrium.eads.net/en/news/tandem-x-ready-for-launch.html