by Tanja Schumann (TU Berlin), March 2025
Currently, there are two main methods by which exoplanets are discovered: The transit method looks for planets by examining the light from stars for brief fluctuations in light. The light fluctuates when an exoplanet passes by – a so-called transit. Nasa’s “TESS” space telescope, among others, uses this method.
The second method is the radial velocity: Regular shifts in the light spectrum of the star reveal a slight wobble of that very star – an indication of the gravity of a planet present.
Callingham and his research team may now have found another method. “Stellar aurora could be a step toward direct observation of exoplanet magnetic fields”, he said. In their study, published in the journal Nature Astronomy, they show that the emissions collected from the red dwarf stars bear resemblance to the interaction between the planet Jupiter and its moon Io. This interaction leads to strong auroras at the planet’s poles.
Credit: freely available