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Space | 12. December 2018 | posted by Manfred Gottwald

TanDEM-X image of Hiawatha Glacier

Credit: DLR
TanDEM-X radar amplitude image of the region around Hiawatha Glacier. The apparent texture is due to the surface structure of the ice and its dynamics.

Glaciers abound on Greenland's coastline; fed by the Greenland ice sheet, they flow towards the Arctic Ocean. In the northwest, Hiawatha Glacier is located at 78.8 degrees north, 67 degrees west. It emerges from a semi-circular lobe at the ice sheet margin and forms a narrow tongue with a length of 10 kilometres extending onto the ice-free Inglefield Land. Hiawatha Glacier’s northern neighbour, the large Humboldt Glacier, is much more widely known. The front of the Humboldt Glacier is over 100 kilometres wide where it flows into the Nares Strait. The TanDEM-X image shows the region around Hiawatha Glacier.

Recently, however, Hiawatha Glacier has received worldwide attention. Some years ago, radar measurements performed as part of NASA’s Operation IceBridge, a campaign to monitor changes in the polar ice caps, revealed a circular depression in the ground underneath the ice where Hiawatha Glacier emerges from the ice sheet. Subsequent surveying by an international research team using a more advanced airborne radar system on board the Polar 6 aircraft operated by the Alfred Wegener Institute (AWI) yielded a more detailed view of that bowl-shaped feature. With a diameter of 31 kilometres and a depth of more than 300 metres, it resembles impact craters on Earth or the solid surface of other celestial bodies. read more

Space | 30. July 2013 | posted by Ralph Kahle

Formation swapping - Comic about the TanDEM-X mission

An exciting manoeuvre awaits us. In early August (6–8 August 2013), the two TanDEM-X mission satellites will be reversing their formation. Until now, the TanDEM-X satellite has been circling around its twin, TerraSAR-X, in an anti-clockwise direction; after the reversal, it will circle clockwise. read more

Space | 01. March 2011

Where and how does ice move in the ocean?

TanDEM-X has now begun routine operations, and is working with TerraSAR-X in bistatic mode and recording data for its global digital terrain model. In this post, I look back at an earlier phase of the mission, when this satellite pair orbited the Earth separated by a mere three seconds or 20 kilometres, and each sensor acquired images independently. read more

Space | 19. October 2010 | 1 Comment

Baptism of fire for the satellite formation

Last Thursday, the two German radar satellites of the TanDEM-X formation finally reached their operational orbit configuration, with only a few hundred metres separating them. In this configuration, they act as a unique radar interferometer in space. The next day, on Friday evening, the instruments were switched on, after many careful checks, to acquire the world's first Digital Elevation Model (DEM) data using a free-flying bistatic Synthetic Aperture Radar (SAR) satellite formation. That same night, the jointly acquired data were received and processed by our operational processing chain. read more

Space | 15. October 2010 | posted by Ralph Kahle | 4 Comments

The satellites have 'eye contact'

This is the moment we have been anticipating for a long time; TerraSAR-X and TanDEM-X finally have 'eye contact'. The final manoeuvre to adjust the close formation was performed on 13 October. Now, the two satellites are orbiting at a distance of less than 400 metres from one another. read more

Space | 27. August 2010

TerraSAR-X and TanDEM-X 'chatting' for the first time

Brasília

Even though the 'chit chat' between the satellites has so far consisted of no more than the exchange of synchronisation signals – "Hello, here I am!" – that is been all that was needed for the first simultaneous imagery to be captured by TerraSAR-X and TanDEM-X. Since 22 July 2010, TerraSAR-X has been flying ahead of TanDEM-X at a distance of just 20 kilometres, in a formation defined for test purposes and which also affords scope for a special series of radar experiments. They have now completed the first ever experiment with bistatic radar involving two satellites flying together in formation. read more

Space | 20. August 2010 | 1 Comment

The face of the Earth

For a month now, we have been acquiring altitude models with the TanDEM-X and TerraSAR-X satellite pair. Already, over 1000 products have come out of our operational processing chain. Alongside many test images, some of the data also give an insight into how humankind has shaped the surface of the Earth – and how the highs and lows around them have determined the course of their lives. read more

Space | 19. August 2010 | 1 Comment

Processing of first TanDEM-X data received at Inuvik

Erhard Diedrich, in charge of the building of the Inuvik satellite station, returned from Canada with his colleagues, a happy man. The inauguration on 10 August was not only moving, but also marked the end of a successful first checkout phase. Over 300 passes of data have been acquired since April this year, among them 60 from the TanDEM-X satellite. read more