Scientists have suggested in a study that radio signals may allow aliens to detect humans on Earth.
Human beings use radio transmitters such as mobile phones and satellite communication services which cause the signals to leak, reported The Sun.
The radars and radios have high-frequency signals that can reach space.
Scientists from the University of Manchester conducted a study in which they used crowdsourced data to simulate radio leakage from mobile towers.
The findings revealed that the Earth's mobile radio signature includes a substantial contribution from developing nations such as Africa.
According to the team, "this is exciting because it highlights the countries' success in moving directly into the digital age."
The team leader of the research Professor Mike Garrett 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."
Professor Garrett maintained that while each system represents low radio powers, the "spectrum of billions of these devices is substantial".
"Current estimates suggest we will have more than 100,000 satellites in low-Earth orbit and beyond before the end of the decade," he added.
"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."
He believed that much-advanced civilisations exist in other spaces.
"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," said Dr Nalini Heeralall-Issur, associate professor at the University of Mauritius.
As the researchers advance in their investigation, they will further look into other sources of Earth's radio leakage, including military radars and Wifi signals.
