Can you measure magnetic field changes on land, in the sea and in the air, from space?


No. The strength and direction of the earth's magnetic field can only be determined by making measurements at the specific location, it can not be 'imaged' remotely. The only method for remote measurements of magnetic fields is by using the Zeeman Effect, and this requires measuring the light from excited atoms located in the magnetic field. This is how astronomers study and map the magnetic field in the sun, and in distant interstellar clouds where the effect can be detected in the 21 centimeter hydrogen-line radiation.


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All answers are provided by Dr. Sten Odenwald (Raytheon STX) for the
NASA IMAGE/POETRY Education and Public Outreach program.