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Soft X rays in the energy regions below 284 eV and between 500 and 1000 eV have been detected on the vicinity of the North Polar Spur. The region of enhanced X-ray emission reported was observed from an Aerobee 150 rocket launched on May 29, 1970, from Woomera, Australia.
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Bunner et al. (1972) studied this question.
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