Stormy 'Space Weather' spawns aurora and gorgeous natural
VLF radio sounds.
Aurora photo taken by Steve McGreevy in northern Manitoba,
Canada on 23 August 1996.
Another aurora photo of red and green aurora taken by Steve McGreevy in northern Alberta,
Canada on 13 August 2000 at 0200 MDT.
Auroral Chorus II CD information
WR-3 hand-held VLF receiver information pages
Science and SoundScapes: Interest in naturally-occurring ELF/VLF radio phenomena such as "whistlers" and "chorus" has enjoyed a rapid resurgence during the past 10 years on the part of academic research via orbiting space-probes and ground-based monitoring efforts, and also notably amongst amateur hobbyists world-wide thanks to easy availability of sensitive receiving equipment. As Solar-Cycle 23 nears its peak (during 2001) increased solar-activity has been spawning great amounts VLF phenomena here on Earth, as it is activity on the Sun and its Solar Wind that help create the great variety of VLF phenomena that we can monitor - whether for research and experimentation, or simply for the enjoyment of listening to yet another realm of nature's beauty!
Most importantly, a great many people who are not really "radio nuts" or "techies" but who love nature and listening to interesting sounds have listened to Natural Radio either live or recorded and have called it the "music of Earth itself." To listen and enjoy Natural Radio, the audio-frequency radio waves must be converted directly to sound frequencies so we can listen to them with our ears. This is what my receiving eqipment does, and the enjoyment of collecting a large recorded library of these phenomena (beginning in June 1989) is my foremost interest.
Lightning storms, Earth's magnetic-field , and the Aurora Borealis and Australis (Northern & Southern Lights) all produce an amazing variety of electromagnetic "sounds," such as sferics (lightning-stroke static), tweeks, Whistlers of countless variety, the incredible "Chorus" chirping, barking and squawking radio "sounds" produced by the the Sun's solar-wind hitting Earth's magnetic-field; various kinds of "Hiss"; bizzarre "wavering-tone" emissions, and other endless variety of fascinating radio sounds to listen to.
This photo is of my van and WR-4b receiver antenna at a VLF listening site in the Black Rock Desert in northwestern Nevada, 22 September 1996. Remote desert locations are far from sources of electrical interference (such as AC power-lines) and are also great listening places, especially above 40 degrees north (geographic) latitude.
The WR-4b receiver's vertical whip antenna of 9 feet (2.6 m) in length is attached to van on its rear door. This is the VLF receiving system and expedition "accomodation" I have used for the past 9 years.
Spectrogram of strong Nevada whistler (19 April 1996 - McGreevy)
Natural VLF radio signals tell a great deal of what is happening with Earth's "near-space weather," that is, what is going on between the Sun and Earth. Invisible weather to our eyes but just as wild and stormy at times as the weather "down here."
Auroral curtains photographed at 0500 UTC on 23 August 1996 in Manitoba, Canada during my SOLAR-MINIMUM VLF RECORDING EXPEDITION. Photo by Stephen P. McGreevy
Many listeners to natural VLF radio note how the majority of these recordings of Earth's beautiful Natural VLF Radio sounds closely resemble biological/vocal sounds made by birds, frogs, whales, seals, etc. (or sci-fi sound effects). As we begin a new Solar-Cycle (#23) and see increasing numbers of sunspots and associated magnetic-storms and disturbances here on Earth, we're already seeing an upsurge in naturally-occurring VLF phenomena. Between now and the sunspot peak in the years 1999 - 2001, we're entering a fabulous time once again to listen to radio signals below 10 kHz.
VLF LISTENER'S HANDBOOK (Text-only version) I have combined the text portions only (no images or hyperlinks) of the THE VLF STORY (see link below too for entire version); The WR-3/3E LISTENING GUIDE; plus a sheet describing the various SOUNDS OF VLF PHENOMENA. Save to your hard-drive and read/print off-line with your web browser. Chock full of about 50(+) pages of information all about Natural ELF/VLF Radio (145K of HTML text as of October 1997)
Another photo of Manitoba aurora - 29 August 1996.
Places where the beautiful Northern Lights can be seen (i.e. northern U.S.
states, all of Canada and Alaska, northern Europe) are supurb places also
to listen to natural radio.