Scientists Discover New Method to Hunt for Hidden Exomoons: Radio Waves

Scientists are continuing their hunt for life and planets beyond our solar system and so far, they've been pretty successful. They've discovered more than 1,800 exoplanets in recent years. That said, they've yet to identify and confirm an exomoon. Now, scientists may have just may have found a way to detect an exomoon with the help of a trail of radio waves.

When Jupiter's magnetic field interacts with its moon, Io, it produces radio wave emissions. In theory, scientists could detect similar emissions from exoplanets and, therefore, detect exomoons. By characterizing the Jupiter/Io dynamic, researchers could use the data and apply to exoplanets.

During its orbit, Io's ionosphere interacts with Jupiter's magnetosphere, which is a layer of charged plasma that protects the planet from radiation. This interaction creates a frictional current that causes radio wave emissions.

"This is a new way of looking at these things," said Zdzislaw Musielak, one of the researchers, in a news release. "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."

The scientists stress that it's important to note when modeling the Io example to other planet/moon pairs that other moons do not necessarily have to have the same volcanic activity as Io to have an ionosphere.

"Larger moons-such as Saturn's largest moon, Titan-can sustain a thick atmosphere, and that could also mean they have an ionosphere. So volcanic activity isn't a requirement," said Joaquin Noyola, lead author of the new paper.

The findings could give researchers a new way to detect these exomoons. While scientists continue their search for life on other planets, it's also possible that moon could support life. This means that finding exomoons and then characterizing them could be crucial for detecting alien life.

The findings are published in The Astrophysical Journal.