The k2p blog

The German aerospace centre announced today that

On 14 October 2010, the radar satellite TanDEM-X moved into close formation with its ‘twin’, TerraSAR-X. Before this, the two satellites were orbiting 20 kilometres apart – a flight time of almost three seconds. Now, there are only 350 metres separating the pair, which means their antennas are able to acquire radar images of the same area simultaneously.

Premiere – TerraSAR-X and TanDEM-X now flying in close formation

The objective of the mission is to create a high-precision, three-dimensional digital elevation model of Earth’s land surface. The project needs the satellites to operate in parallel for a period of three years. The transition to close formation flight marks the beginning of the final preparatory stage of the TanDEM-X mission. The routine operations phase is due to start in early January next year.

The TerraSAR-X and TanDEM-X orbit trajectories, patented by DLR researchers, are like the strands of a double helix – they circle around one another without crossing. The team of scientists based in DLR Oberpfaffenhofen took just three days to carry out the approach in preparation for the final formation flight. “First, we had to manoeuvre TanDEM-X to reduce its orbital period, so that the satellite could ‘catch up’, reducing the 20 kilometre gap between it and TerraSAR-X. After two further manoeuvres we brought the distance between the pair down to 350 metres,” explains DLR flight dynamics expert Ralph Kahle.

The reduced distance between the satellites means that the two radar systems can be synchronised for the first time. TerraSAR-X and TanDEM-X can also monitor each other’s ‘health’ via an inter-satellite link. “This is completely uncharted territory. Never before have two satellites worked in such close formation over a period of several years,” says Manfred Zink, Project Manager for the TanDEM-X Ground Segment. Eckard Settelmeyer, Director of Earth Observation and Science at Astrium, adds: “This dual mission will give another boost to satellite-supported applications and science.”

Read the whole article:

http://www.dlr.de/en/desktopdefault.aspx/tabid-1/117_read-27086/

Tags: Digital elevation model, Satellite, satellite mapping, TanDEM-X, TerraSAR-X

This entry was posted on October 15, 2010 at 1:54 pm and is filed under Cartography, Geosciences, Germany, Space. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.