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Swift
2014-Aug-12, 03:39 PM
R&D Magazine (http://www.rdmag.com/news/2014/08/follow-radio-waves-exomoons?et_cid=4095266&et_rid=54636800&type=headline)


Scientists hunting for life beyond Earth have discovered more than 1,800 planets outside our solar system, or exoplanets, in recent years, but so far, no one has been able to confirm an exomoon. Now, physicists from The Univ. of Texas at Arlington believe following a trail of radio wave emissions may lead them to that discovery.

Their recent findings, published in The Astrophysical Journal, describe radio wave emissions that result from the interaction between Jupiter’s magnetic field and its moon Io. They suggest using detailed calculations about the Jupiter/Io dynamic to look for radio emissions that could indicate moons orbiting an exoplanet.

“This is a new way of looking at these things,” said Zdzislaw Musielak, professor of physics in the UT Arlington College of Science and co-author of the new paper. “We said, ‘What if this mechanism happens outside of our solar system?’ Then, we did the calculations and they show that actually there are some star systems that if they have moons, it could be discovered in this way.”



Link to the Journal (http://iopscience.iop.org/0004-637X/791/1/25)


In the Jupiter-Io system, the moon's motion produces currents along the field lines that connect it to Jupiter's polar regions. The currents generate and modulate radio emissions along their paths via the electron-cyclotron maser instability. Based on this process, we suggest that such modulation of planetary radio emissions may reveal the presence of exomoons around giant planets in exoplanetary systems. A model explaining the modulation mechanism in the Jupiter-Io system is extrapolated and used to define criteria for exomoon detectability. A cautiously optimistic scenario of the possible detection of such exomoons around Epsilon Eridani b and Gliese 876 b is provided.