30-Year-Old Prediction Verified
The Extreme Ultraviolet Imager (EUV) on the IMAGE spacecraft is providing the first
global images of the plasmasphere.
The donut-shaped plasmasphere is the high altitude extension of the Earth's ionosphere.
During times of enhanced geomagnetic activity, the plasmasphere is dramatically reduced in size.
Where does the plasma go?
EUV has obtained images showing plasma tails streaming away from the plasmasphere.
These images confirm a 30-year-old model of solar-wind-driven convection of plasma in the
magnetosphere [Grebowsky, JGR 75, 4329 (1970); Chen et al., JGR 80, 968, (1975)].