Are we attracting aliens to Earth?
You’re at a busy airport like London Heathrow, Paris Charles de Gaulle or Amsterdam Airport Schiphol. Crowds and noise, long queues, fear of flying, baggage collection and transfer times are some of the things going through your mind as you’re waiting to take off or just passing through.
We’re here!
What hasn’t crossed your mind though is that you may be inadvertently alerting aliens to our existence. Wait, what? Yes, extraterrestrial eavesdroppers somewhere out there could potentially be listening. But there’s no immediate need for panic! Radar systems used by civilian airports and military installations to keep our skies safe are broadcasting signals to the cosmos and revealing our existence. This is because airport radar in all parts of the world leaks electromagnetic energy into space. This signal gives our location on Earth and is strong enough to be picked by aliens as far as 200 light years away. How far is that? About 1.89 quadrillion kilometres. This range covers over 120 000 stars. Of course, intelligent life within this range could be sending the same leaked message to our planet! Proxima Centauri b, the closest potentially habitable exoplanet, is just 4.2 light years away. All this is based on the assumption that the extraterrestrials have high-tech radio telescopes that at least match ours. A research team led by Ramiro Saide of the University of Manchester in the United Kingdom (UK) developed a model to simulate radar signals from major hubs like Heathrow and John F. Kennedy International Airport in New York, as well as from military radar systems. The researchers simulated how these signals spread out from our planet as they travel through space. Next, they worked out how detectable these signals would be from six nearby stars, including Barnard’s Star – the fourth nearest star to Earth at around 6 light years away. The study(opens in new window) was presented at the Royal Astronomical Society’s National Astronomy Meeting in Durham, UK, on 8 July. “Our findings suggest that radar signals – produced unintentionally by any planet with advanced technology and complex aviation system – could act as a universal sign of intelligent life,” commented Saide in a news release(opens in new window).
Not sending the wrong signal
“By learning how our signals travel through space, we gain valuable insights into how to protect the radio spectrum for communications and design future radar systems,” explained co-researcher Michael Garrett, professor at the University of Manchester. Garrett stressed the usefulness of the techniques used in the study. “The methods developed for modelling and detecting these weak signals can also be used in astronomy, planetary defence, and even in monitoring the impact of human technology on our space environment.” “In this way, our work supports both the scientific quest to answer the question ‘Are we alone?’ and practical efforts to manage the influence of technology on our world and beyond,” Saide concluded. All these years, we’ve been going to great lengths to find alien life. Never did we expect that they might find us first thanks to some advertising courtesy of airports!