Radio Observations as an Exoplanet Discovery Method

  • T. Joseph W. LazioEmail author
Reference work entry


Detection of radio emission from Jupiter was identified quickly as being due to its planetary-scale magnetic field. Subsequent spacecraft investigations have revealed that many of the planets, and even some moons, either have or have had a planetary-scale magnetic field. In the case of the Earth, Jupiter, Saturn, Uranus, and Neptune, the magnetic field is generated by dynamo processes within the planet, and an interaction between the solar wind and their magnetic fields generates intense radio emission via the electron cyclotron maser instability. Not only may the radio emissions be a means for discovering extrasolar planets, because magnetic fields are tied to the properties of planetary interiors, radio emissions may be a remote sensing means of constraining extrasolar planetary properties that will be otherwise difficult to access. In the case of terrestrial planets, the presence or absence of a magnetic field may be an indicator for habitability. While no extrasolar planets have yet been detected in the radio, new ground-based telescopes and new possibilities for space-based telescopes provide promise for the near future.


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Copyright information

© This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2018

Authors and Affiliations

  1. 1.Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaUSA

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