Seeing the world with different eyes - that's often just said like that.
The new German environmental satellite "EnMAP" (Environmental Mapping and Analysis Program") is supposed to be able to do just that - although of course it has no eyes, technical equipment is at work inside.
Launched on April 1st with a "Falcon 9" rocket from SpaceX in the US state of California, the device sent its first image to earth a few days ago.
It shows a strip about 30 kilometers wide and 180 kilometers long over Istanbul on the Bosphorus in Turkey, recorded from an altitude of around 650 kilometers.
What is special about "EnMAP" is not the resolution of the image, which is not particularly high.
The new satellite scores in another area: Normal digital cameras differentiate between three different colors for their images – red, green and blue.
So-called multispectral cameras evaluate up to ten areas.
»EnMAP«, on the other hand, uses 242 wavelength ranges of light.
In this case one speaks of a hyperspectral camera.
And their use in environmental monitoring has advantages: Every material on the earth's surface reflects sunlight in a characteristic way.
A so-called spectral signature can be observed, an optical fingerprint if you will.
Ideally, it is not only easier to distinguish which parts of the earth's surface are covered with, say, rye - and which are covered with terraced houses.
It should also be possible to see whether the plants are suffering from drought stress or pests, whether lakes and coastal waters are polluted with pollutants or plastic waste.
Anna Christmann, the federal government's coordinator for aerospace, calls the satellite "an excellent example of how the most modern space technology can be used for the benefit of mankind and the environment".
Mission duration at least five years
In fact, a whole armada of Earth observation satellites keeps an eye on our planet at all times.
In addition to the US »Landsat« program, the European »Sentinels« are also important.
But while the Americans already had a hyperspectral satellite from 2000 in the form of the »Earth Observing-1«, which has since been decommissioned, the European observation program is only to have this capability with the »Chime« observatory towards the end of the decade.
After all, Italy launched a hyperspectral satellite called »Prisma« in 2019.
The new German satellite is now expected to collect vast amounts of data within at least five years.
It flies over every point on earth every 27 days.
If the camera is aimed at interesting targets, significantly shorter intervals of four days are also possible.
delays and additional costs
The German Research Center for Geosciences Potsdam (GFZ) has assumed the scientific management of the mission.
The inspectors at the German Aerospace Center (DLR) in Oberpfaffenhofen are responsible for satellite operation and monitoring.
"EnMAP" is still being calibrated and set precisely, says Sebastian Fischer, project manager at the German Space Agency at DLR.
"But the first images give us an excellent foretaste of what scientists all over the world can expect." .
But the truth is that »EnMAP« started more than ten years late.
And the satellite has also become three times more expensive than originally agreed.
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