It was an ordinary autumn afternoon pottering around the back yard for Doug Harrison when an engine-like roar suddenly drowned out the sound of the leaf blower.

“It sounded like two jets were directly above my house,” said Harrison, 50, a former steelworker from Jackson Township, a rural community in Pennsylvania. “I swear to God I thought this is it, those jets are going to crash into my property.”

Residents for miles around exchanged frantic messages while scouring flight radar and emergency service scanner apps for clues, as the township’s volunteer firefighters sped past, sirens blazing. But this was no terrorist attack or aviation calamity. The deafening noise and the foul smell of rotten eggs that followed was a massive methane leak at a nearby gas storage facility, an unfolding climate catastrophe captured by satellites in space.

Over the next few weeks, more than a billion cubic feet of methane and other toxins were spewed into the atmosphere from a failed storage well at an ageing fossil-fuel facility operated by Equitrans Midstream Corporation on Rager Mountain.