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Updated: Jul 12, 2026

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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Radio Reflection by Free Radicals in Earth's Atmosphere.
Summary
Free radicals in Earth's ionosphere reflect radio signals, matching predictions for magnetic-dipole transitions. This method may detect magnetic atoms, ions, and molecules in planetary atmospheres.
Area of Science:
- Geophysics
- Atmospheric Science
- Radio Physics
Background:
- Earth's ionosphere contains free radicals that interact with electromagnetic waves.
- Previous research has explored radio wave propagation through planetary atmospheres.
Purpose of the Study:
- To investigate the reflection of megacycle-per-second radio signals by free radicals in Earth's ionosphere.
- To assess the potential of using radio signal reflections for detecting magnetic atoms, ions, and molecules in planetary atmospheres.
Main Methods:
- Utilizing observations from the Canadian satellite Alouette II.
- Employing a topside ionosonder to analyze radio signal reflections.
Main Results:
- Observed radio signal reflections with intensities consistent with induced magnetic-dipole transitions.
- Demonstrated the feasibility of detecting specific ionospheric components via radio wave interactions.
Conclusions:
- The reflection intensity aligns with theoretical predictions for magnetic-dipole transitions.
- Radio signal reflection presents a viable method for detecting magnetic species in planetary atmospheres.
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