‘Electrosensitive’ people are flocking to the West Virginian home of a deep-space telescope, attracted by the rules prohibiting phones, TVs and radios. But, as Ed Cumming reveals, their arrival means Green Bank is far from peaceful

Up and up the roads to Green Bank went, winding into the West Virginian hills as four lanes thinned to one. It was early March and snow was still spattered on the leaf mould between the firs and larches. Hip-hop and classic rock radio stations were gradually replaced by grave pastors and bawdy men twanging banjos and, eventually, they too faded to crackling white noise. The signal pips on my phone hollowed out. I was nearly there.

Over a crest in the road was the cause of the electronic silence: the National Radio Astronomy Observatory (NRAO), an array of radio telescopes set against the indigo vastness of the Blue Ridge Mountains. These giant white ears are cocked to interstellar whispers: the formation of stars, nebulae and supernovae. So sensitive are the devices, and what they are listening for so faint, that even tiny signals nearby can be disruptive: a badly fitted microwave or a faulty electric blanket. It’s like trying to eavesdrop across a room while listening to heavy metal in your earphones.