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Energy question of the week: What is the best way to harness solar energy?

26. July 2010, 11.25
On average, sunlight illuminates every single square metre of the Earth with 1340 watts of power. Measured on human timescales, this energy source is infinite; it warms our planet, enables plants to grow and is the engine driving the winds and weather. But which technology is best able to harness the power of sunlight?
Jan Oliver Löfken
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Jan Oliver Löfken
 
 

The first 3D experiment

22. July 2010, 10.30
It was during a sleepless night, with hardly any drop in the midsummer temperatures, when the idea for a radar experiment with both satellites, TerraSAR-X and TanDEM-X occurred: “What if we could prove that interferometry is possible with two satellites even before the final formation is reached?”
Gerhard Krieger
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Gerhard Krieger
 
 

Energy question of the week: Does the oil spill in the Gulf of Mexico mean the end of deep sea drilling?

19. July 2010, 11.52
Since disaster struck the Deepwater Horizon drilling platform in the Gulf of Mexico on 20 April 2010, up to nine million litres of crude oil have been gushing into the sea every day. It remains to be seen whether the recently installed 40-ton cap can really stop the majority of the oil flowing from the wellhead, 1500 metres under the sea. The spill will only be stopped definitively when the relief wells are completed in mid-August. But is this catastrophe the beginning of the end for deep sea drilling?
Jan Oliver Löfken
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Jan Oliver Löfken
 
 

Approach in orbit; busy times in Neustrelitz

16. July 2010, 20.00
Tirelessly, TanDEM-X is acquiring data while moving ever closer to the TerraSAR-X satellite. As yet, the first flight formation is not set up and thus no interferometric processing is possible. All data received by the TanDEM-X ground station network are transferred to Neustrelitz, where they are processed into SAR images like the operational ones from TerraSAR-X.
Birgit Schättler
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Birgit Schättler
 
 

Stress tests in space and rivers of sand

14. July 2010, 14.02
As ground teams prepared for the formation flight of TanDEM-X and TerraSAR-X, TanDEM-X was put through its paces in the last week before approach. The instrument team ran a set of hot/cold tests to check the instrument’s performance limits by first allowing the radar system to cool down and then running it at full load. This was followed by tests in which a large number of randomly targeted radar images of the Earth’s surface were used to test the reliability of the reception and processing systems. The images acquired during these tests include a number of very puzzling pictures.
Thomas Fritz
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Thomas Fritz
 
 

Art in space – or, how to set up a formation

12. July 2010, 15.35
On its launch date, 21 June 2010, roughly 16,000 kilometres separated TanDEM-X from its twin satellite, TerraSAR-X. Now, that distance has shrunk to just 2000 kilometres. The time has come for the relative movement between the two satellites to be slowed down, and for them to be set up for formation flying. To accomplish this, the Flight Dynamics Group at the German Space Operations Center (GSOC) will carry out a total of 10 orbital manoeuvres over the next eight days.
Ralph Kahle
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Ralph Kahle
 
 

Energy question of the week: Can the human body be used as a power plant?

12. July 2010, 09.53
A human being performing light physical activity needs between 1800 and 3000 calories of energy each day. With hard work and sports, this energy requirement can double. Is it possible to obtain usable electricity or heat from this energy expenditure?
Jan Oliver Löfken
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Jan Oliver Löfken
 
 

Energy question of the week: How does a solar cell work?

05. July 2010, 10.19
At present, commercially available solar cells made from polycrystalline silicon operate with an efficiency of 20 percent. Special solar cells composed of other semiconductors such as gallium arsenide have already passed the 40 percent efficiency barrier. In contrast, cells based on organic materials or pigments convert only 10 percent of the sunlight into electrical current at best. All of these use the photovoltaic effect, but what actually happens in the process?
Jan Oliver Löfken
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Jan Oliver Löfken