A “coherent” radio signal has been detected from an alien planet, suggesting it may be suitable for habitability. This signal indicates that the planet has its own magnetic field, considered essential to support life on a particular world.
On Earth, our magnetic field protects us from high-energy particles and plasma emitted by the Sun. Thus, any form of extraterrestrial life would likely depend on a similar field for protection. But until now, researchers have struggled to confirm whether distant rocky planets have their own magnetic fields, making it difficult to determine whether a planet can harbor life.
Now a new candidate – YZ Ceti b, a rocky planet that orbits a star about 12 light-years away – has emitted a repeating radio signal from the star and appears to be influenced by the planet. The radio waves detected by the researchers appear to be generated when the star interacts with the magnetic field of its planets. With the two being so close to each other, this new candidate is an ideal pair to test theories about detecting such magnetic fields at such a distance.
The researchers described this effect as similar to the Northern Lights, which occur on Earth when high-energy particles from the Sun interact with our atmosphere. “We’re actually seeing the aurora on the star – that’s what this radio emission is,” said Sebastian Pineda, an astrophysicist at the University of Colorado and one of the researchers who detected the signal. “There should also be an aurora on the planet if it has its own atmosphere.”
“The search for potentially habitable or life-bearing worlds in other solar systems depends in part on our ability to determine whether rocky, Earth-like exoplanets actually possess magnetic fields,” said program director Joe Pesce. for the National Radio Astronomy Observatory. “This research not only shows that this particular rocky exoplanet likely has a magnetic field, but also offers a promising method to discover more.”
These results are presented in a new paper, “Coherent radio emissions from the known M dwarf planetary host YZ Ceti”, published in Nature Astronomy.