Image of IMAGE in 

Echoes From the Plasmasphere are Observed for First Time.


Radar speed detectors are used by police to measure a car's speed. Using similar radar-like pulses the IMAGE satellite probes the invisible plasma near Earth. As it passes through the plasmapause, echoes from IMAGE's powerful radio transmitter can be detected. IMAGE scientists believe these echoes are guided by plasma 'ducts'. These ducts act like invisible pipes that channel the radio signals along Earth's magnetic field from pole to pole.

(2002: D. L. Carpenter, M. A. Spasojevic, T. F. Bell, U. S. Inan, B.W. Reinisch, I. A. Galkin, R. F. Benson, J. L. Green, S. F. Fung, and S. A. Boardsen)

Related IMAGE Discoveries

Additional Information

Plasmapause - The boundary of the plasmasphere. Inside this boundary, plasma rotates with Earth. Outside, the plasma orbits Earth at slower speeds.

Duct- Radio waves can be reflected in a plasma like light is reflected within a fiber optic cable. These radio channels within a plasma often align with magnetic field lines.

IMAGE experiments
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Dr. S. Odenwald,, +1-301-286-6953
NSSDC, Mail Code 630, NASA Goddard Space Flight Center, Greenbelt, MD 20771
NASA Approval: J. L. Green,
Rev. 1.0.0, 24 April 2003, EVB II