SETI study suggests stellar activity may distort alien radio signals before they reach Earth
A new study from the SETI Institute suggests that signals from distant civilisations may be altered long before they ever reach Earth. Researchers found that the environments surrounding stars could significantly distort the narrowband radio signals most SETI programmes rely on. These signals are usually expected to appear as sharp, highly concentrated spikes in frequency, making them easier to separate from natural cosmic background noise.
The study focuses on what happens much closer to a signal’s origin than previous models considered. Conditions such as turbulent plasma in stellar winds and explosive activity like coronal mass ejections can reshape radio waves as they form. That process can spread the energy of a signal across a wider range of frequencies, weakening the distinctive signature scientists look for.
To test how significant this effect might be, researchers turned to a more familiar source of data: radio transmissions from spacecraft operating within our own solar system. These signals, already affected by solar plasma, were used to model how similar distortions might behave in other stellar environments.
The results provide a framework for estimating how much signal broadening could occur depending on the type of star and the surrounding space weather conditions. This is particularly relevant for active systems where plasma fluctuations are more extreme.
The study highlights M-dwarf stars, which make up roughly 75% of all stars in the Milky Way, as especially likely to distort narrowband signals before they can escape their systems.
Researchers suggest that future SETI work may need to widen its search parameters to include broader signal patterns rather than focusing only on ultra-narrow frequency spikes.
The work is supported through the SETI Institute’s STRIDE programme, funded by the Franklin Antonio Bequest, which supports research into emerging scientific questions and technological development.
Explore more investigations into how space science is reshaping what we understand about the universe and what might still be hidden within it. EyeOnLondon continues to report on the science, culture and technology shaping how we understand life beyond Earth.
Follow us on:
Subscribe to our YouTube channel for the latest videos and updates!
We value your thoughts! Share your feedback and help us make EyeOnLondon even better!
