Astronomers decode what Earth may look like to advanced aliens

‘There’s every chance advanced civilisations are out there, some may be capable of observing human-made radio leakage’

Any alien civilisation near Earth will have to be more technologically advanced than humans to find them, reveals a new study.

Researchers, including those from Manchester University, used crowd-sourced data to simulate leakage of radio signals from mobile towers and predict what an extraterrestrial civilisation might find from various nearby stars, including one that is six light years away from Earth.

Any hypothetical civilisations within 10 light years away from our planet that match human technology, and that are equipped with a receiving system comparable to Earth’s, cannot depend on current mobile tower radio signals leakages into space to detect human life, said the findings published in the journal MNRAS.

Unless an alien civilisation is much more advanced than humans, they will find it difficult to detect current levels of mobile tower radio leakage from Earth, the study said.

The scientists generated models displaying the radio power that an alien civilisation may likely receive as Earth rotates and towers rise and set.

They also suggested the detectability of mobile systems on Earth will increase substantially as more powerful broadband systems are adopted across the planet.

The study also found the Earth’s mobile radio signature includes a substantial contribution from Africa, shedding light on the continent’s transition into the digital age after bypassing the landline era.

“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 around the world is profound,” study co-author Mike Garrett from the Manchester University said.

“While each system represents relatively low radio powers individually, the integrated spectrum of billions of these devices is substantial,” Dr Garrett said.

Scientists are currently planning to extend their research to include other contributors to Earth’s radio leakage signature.

“I believe that there’s every chance advanced civilizations are out there, and some may be capable of observing the human-made radio leakage coming from planet Earth,” said Nalini Heeralall-Issur, another author of the study.

In further studies, researchers hope to assess the signal leakage from powerful civilian and military radars, new digital broadcast systems, Wi-Fi networks, individual mobile handsets and satellite swarms like Elon Musk’s Starlink system that are being launched into low Earth orbit.

“Current estimates suggest we will have more than one hundred thousand satellites in low Earth orbit and beyond before the end of the decade,” Dr Heeralall-Issur said.

“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 civilization with the right technology,” she said.