Mega constellation of SpaceX, Starlink, continues to grow rapidly. The technology developed by the American company aims to bring high-speed internet anywhere on the planet. However, a recent study (ref.) highlights an extravagant possibility: could all the Starlink satellites increase the chances of Earth being detected by aliens?
The study has determined that the radio signals generated by the mobile towers on Earth are likely detectable by nearby systems such as the Barnard’s Star, which is only six light-years away. Currently, the radio signals are still weak, but their power will increase in tandem with the growing number of SpaceX satellites.
The study utilized data from radio signals, simulating a reception point away from our planet. Among the analysts was Ramiro Saide, an intern at the Hat Creek Radio Observatory of the Search for Extraterrestrial Intelligence Institute (SETI), located north of San Francisco.
Saide “generated models that show the radio power these civilizations would receive as the Earth rotates and the towers rise and set” wrote the SETI Institute in a publication (ref.). The detectability of Earth’s radio signals could be weak, warn the researchers unless these alien civilizations have more sensitive receiving systems than ours.
Satellite networks for mobile traffic
While traditional radio broadcast traffic is declining, more powerful radio beacons are emerging to support and enhance new mobile communications. Additionally, countries in the Global South are contributing more to radio traffic compared to previous decades.
“I’ve heard many colleagues suggest that Earth has become increasingly silent in recent years, a claim that I have always contested” said team leader Mike Garrett, a professor at the University of Manchester in England and director of the Jodrell Bank Centre for Astrophysics. “While it is true that we have fewer powerful TV and radio transmitters today, the proliferation of mobile communication systems worldwide is profound. Although each system individually represents relatively low radio power, the integrated spectrum of billions of these devices is substantial”.
SpaceX recently surpassed 4,000 active individual Starlink satellites in orbit and hopes to increase that number to at least 40,000. If SpaceX and other companies send tens of thousands of satellites, the artificial terrestrial radio signal will become much easier to detect. “Current estimates suggest that we will have over 100,000 satellites in low Earth orbit (LEO) before the end of the decade” Garrett added. “The Earth is already unusually bright in the radio part of the spectrum. If the trend continues, Starlink and similar satellite networks will make us visible to aliens who possess the right technology”.