A new study investigated whether extraterrestrial civilizations could discover humanity by detecting radio signals leaking from Earth’s mobile phone towers.
The team simulated leakage from cell towers around the world in an effort to determine whether or not advanced aliens from nearby stars would be able to detect it using apparatus comparable to our own.
“In terms of detectability, we conclude that any nearby civilization located within 10 light-years of Earth and equipped with a comparable receiving system to the GBT [Green Bank radio telescope] would not detect Earth’s mobile tower leakage,” the team concluded.
Thus, Earth’s technology cannot detect analogous alien signals.
Scientists speculate that alien civilizations may soon be able to pick up on our cell phone signals.
“However, mobile systems are in their infancy, and the future development of this technology (e.g., 5G systems and beyond) suggests that this component of the Earth’s leakage will continue to increase in power over time,” the authors write in their paper. “If the leakage can be detected, an extraterrestrial observer would be able to discern various details about our planet’s nature and the distribution of technology on its surface.”
According to the team, this would include the ability to construct a model of Earth displaying the distribution of land, vegetation, oceans, and ice.
Professor Mike Garret, director of the Jodrell Bank Centre for Astrophysics at the University of Manchester and lead author of the study, said in a statement, “I’ve heard many colleagues suggest that the Earth has become increasingly radio quiet in recent years, a claim that I’ve always disputed.”
“Although it is true that we have fewer potent TV and radio transmitters today, the global proliferation of mobile communication systems is significant. While individual systems have relatively modest radio powers, the combined spectrum of billions of these devices is substantial.”
Naturally, aliens with more sophisticated listening devices would have a greater chance of picking up our stray signals, and the likelihood of this occurring increases as our own technology advances.
Garrett added, “According to current estimates, we will have more than one hundred thousand satellites in low Earth orbit and beyond by the end of the decade.” “The Earth is already unusually bright in the radio portion of the electromagnetic spectrum; if the trend continues, we could become easily detectable by any technologically advanced civilization.”