Scientists from The University of Manchester the University of Mauritius used crowd sourced data to simulate radio leakage from mobile towers to determine what alien civilisations might detect from various nearby stars, including Barnard’s star, six light years away from Earth.
The research, published in the Monthly Notices of the Royal Astronomical Society journal, found that only more technologically advanced civilisations would be able to detect the current levels of mobile tower radio leakage from Earth. However, as most alien civilisations are likely to have more sensitive receiving systems and as we move towards more powerful broadband systems on Earth, the detectability of humans from other intelligent beings will become more and more likely.
Professor Mike Garrett, Team Leader of the project and Director of Jodrell Bank Centre for Astrophysics at The University of Manchester, said: "I’ve heard many colleagues suggest that the Earth has become increasingly radio quiet in recent years - a claim that I always contested.
"Although it’s true we have fewer powerful TV and radio transmitters today, the proliferation of mobile communication systems around the world is profound. While each system represents relatively low radio powers individually, the integrated spectrum of billions of these devices is substantial.
"Current estimates suggest we will have more than one hundred thousand satellites in low Earth orbit and beyond before the end of the decade. The Earth is already anomalously bright in the radio part of the spectrum; if the trend continues, we could become readily detectable by any advanced civilisation with the right technology".
The Earth is already anomalously bright in the radio part of the spectrum; if the trend continues, we could become readily detectable by any advanced civilisation with the right technology.
The models, which demonstrate the signals that aliens may receive from Earth, were generated by Ramiro Saide, an intern at the Search for Extra-terrestrial Intelligence (SETI) Instution’s Hat Creek Radio Observatory and M.Phil student at The University of Mauritius.
The simulations also show that the Earth’s mobile radio signature includes a substantial contribution from developing countries, including Africa, which the scientists say is an exciting development and highlights its success in bypassing the landline stage of development and moving directly into the digital age.
Dr Nalini Heeralall-Issur, Saide’s supervisor and Associate Professor at the University of Mauritius, said: "Every day we learn more about the characteristics of exoplanets via space missions like Kepler and the Transiting Exoplanet Survey Satellite, with further insights from the James Webb Space Telescope. I believe that there’s every chance advanced civilisations are out there, and some may be capable of observing the human-made radio leakage coming from planet Earth."
Next, the research team is keen to extend their research to include other contributors to the Earth’s radio leakage signature, such as powerful civilian and military radars, new digital broadcast systems, Wi-Fi networks, individual mobile handsets and the swarm of satellite constellations now being launched into low Earth orbit, such as Elon Musk’s Starlink system.