Original URL: http://www.theregister.co.uk/2012/12/18/earth_radios_loud/

Shh! Proxima Centauri can hear us!

Australian researchers test Earth's outbound radio noise

By Richard Chirgwin

Posted in Science, 18th December 2012 04:07 GMT

In the unlikely case that Proxima Centauri is inhabited, that its inhabitants are technologically developed ahead of Earth, and its inhabitants actually care about us, its media might is just catching up with the stories of 2008.

Nearby and more contemporaneously, an ANU researcher, Ben McKinley, has run a calculation for humanity’s radio emissions, and concludes that we’re loud enough to be detected from Proxima.

McKinley and fellow researchers from CAASTRO – the Centre for All-sky Astrophysics – used signals collected at Western Australia’s Murchison Wide-Field Array to come up with the conclusion.

Instead of using the remote radio-telescope to listen for distant and ancient stars and galaxies, the scientists measured the much more prosaic TV and FM radio station reflections (in the 87.5 to 108 MHz band) reflected from the Moon.

“What we actually found was that the moon is reflecting every breaking news story, Top 10 hit, football score, press conference and soap opera, mixed together in a noisy echo of all the Earth’s FM radio signals played simultaneously,” McKinley said in the ANU media release.

McKinley told The Register the signals are strong enough to tell Proxima’s hypothesized inhabitants (Proxmen? Proxers? Proximates?) we’re here, if they possessed a telescope equivalent to Earth's under-construction Square Kilometer Array. However, separating any useful information from the mass of signals sharing the same radio band would pose something of a challenge. ®