Strange noises in Sweden thought to be caused by Northern Lights

Tour guide records noises sounding like ‘Star Wars blasters’

The Aurora Borealis or Northern Lights illuminate the night sky, near the town of Kirkenes in northern Norway

A tour guide has recorded an unusual sound in the north of Sweden that has been likened to the noise emitted by a fictional gun from the Star Wars films - but he believes it comes from the Northern Lights.

Oliver Wright, a photographer and tour guide working for Lights Over Lapland, heard what he described as a rat-a-tat swooshing sound while out with a group of people on Christmas Day.

“I was standing beneath an intense display of auroras in Abisko, Sweden, when I heard something that sounded like Star Wars blasters,” he told Spaceweather.com.

The photographer said the sounds appeared to be coming from nearby powerlines, and that people around him heard the noise, too. He then “rushed closer to the power lines and was able to record a sample using my iPhone”.

Mr Wright said the sound grew louder as he approached the power lines and fainter as he walked away. He had heard the sound three times before on previous trips, each time while close to a power line, but this was the first time he recorded the strange swooshing (listen below).

The sound could have been created by “electrophonic transduction,” according to Spaceweather.com, which is created by the conversion of electromagnetic energy into mechanical motion. This could cause currents to flow through the nearby powerlines with enough force to make them shake and emit noise.

“At the time of the Christmas aurora outburst, magnetic fields around Abisko were seething with activity. Strong low-frequency currents can literally shake objects, launching acoustic vibrations into the air,” astrophysicist Dr Tony Philips said, The Local reported.

After Mr Wright uploaded his own sound recording from Christmas Day online, one person agreed with the photographer’s description that the swooshing was akin to the sound emitted from a Star Wars blaster gun, and claimed that they knew “exactly” how it was created. “It’s high tension electrical lines undulating in the wind and rocking against their pinions,” user Douglas Bryendlson claimed.

“This is exactly how Star Wars sound designer Ben Burtt created those blaster sounds in the first place,” he wrote, posting a video of someone re-creating the sound effect from the films by banging a rock against a large metal cable of a radio tower.

Mr Wright is not the first person to have been curious about the sounds of the aurora borealis, however. For more than a century there have been reports of sounds such as a faint hissing or crackling associated with the Northern Lights that have largely been dismissed as hearsay, according to National Geographic. But Finnish researcher Unto Laine has studied the sounds for more than 10 years and believes the lights may well cause clapping sounds, and he has a theory as to why.

“In history there are thousands of relevant observations, but recordings also exist that consists of many different type of sounds described by observers around the world such as crackling, clapping, popping, booms and low frequency noise,” Mr Laing said.

He believes that the sounds are produced during intense displays of the aurora borealis and when there are cold, clear and calm weather conditions.

Speaking to LiveScience Mr Laing claimed the sounds can be created when a layer of relatively warm air becomes blanketed over a layer of cold air near the Earth’s surface. Electrical charges then build up in the warm layer of air while opposite charges build in the cold layer, and when an intense aurora display appears over these layers it can create geomagnetic disturbances that cause the electricity to discharge and create sounds, he said.