In the past, space physicists have had to rely on many different research satellites, and even weather satellites, to measure the magnitudes and changes in the energetic particles in the magnetosphere. These measurements were always of the particles located where the spacecraft was in its orbit. Not all of the satellites available at a given time observed exactly the same populations of particles at the same time, and their orbital locations were often so radically different that the near-earth environment was very sparsly sampled. Some people have likened this situation to trying to understand the national economy by looking at the financial records of 50 people in different towns across the country.
The IMAGE satellite makes remote measurements of particle populations within the entire magnetosphere, and updates this information every 5 minutes. This lets space scientists, for the first time, see the 'big picture' all at once, rather than very limited local measurements at far-flung points in space. The IMAGE data can still be compared to the local in situ observations made by existing satellites, but provides a global point of view which lets IMAGE monitor large-scale changes and flows of particles.
See the original IMAGE Mission Proposal for more details.
Return to the IMAGE home page.
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