A few seconds of Arborealis. The total audio loop is about 9.5 minutes.

2023. Arborealis is a light and sound installation designed to be presented in the forest at night.

The piece uses Very Low Frequency recordings of atmospheric radio noise, along with synchronized lights against a background of trees to create an entrancing and meditative atmosphere.

The plaque reads:

These sounds are recordings of Very Low Frequency (VLF) radio emissions from the Earth’s atmosphere, converted from radio waves into sound waves. The crackling sounds are radio emissions from lightning happening anywhere within about 3000 miles. The swishing and bird-chirp-like noises are called “dawn chorus” or “auroral chorus”. These signals are created by disturbances to Earth’s magnetic field due to emissions coming from the sun – the same phenomena that also create the aurora. There are numerous reports of people who have directly heard noises associated with auroral activity. Scientists aren’t sure what the source of these sounds might be.
This recording was made in Saskatchewan on 30th June 2001 by a prolific VLF radio enthusiast named Stephen P. McGreevy who has released hundreds of recordings, including this one, into the public domain.1

Arborealis was funded in part by a grant from Ignition Northwest. Thanks to them and also to Shelly Farnham and Jeffrey Larson for their assistance.

  1. Auroral Chorus V: Sferics Anthology & Radio DX on Internet Archive ↩︎