The Earth pulses with a special kind of resonant wave. The Schumann Resonance has long been dubbed 'the Earth's heartbeat,' and it has only been spotted from below. Recently, though, satellites have found signs of this electromagnetic heartbeat leaking up into space.
The heartbeat of the earth goes at about eight cycles per second. Like many other heartbeats, it's regulated by electricity. When lightning strikes the earth, it creates electromagnetic waves in the atmosphere. These waves are caught between the ground and the upper atmosphere, sixty miles up. Most of these waves are dampened and shake themselves to nothing.
Others, with just the right wavelength and frequency, just keep going. The wavelength is the circumference of the earth (or twice the circumference, or three times, or four, and so on). This means that the troughs of these waves will always line up, as will the crests. When crests combine, they get bigger. And with lightning hitting the earth over four million times a day, these waves keep getting the boosts they need. The waves don't sweep across the surface of the earth. Instead they're like standing waves, that just pulse at their troughs and crests - a resonant heartbeat. Scientists call this heartbeat The Schumann Resonance, and always thought it was confined to the earth. It had to be trapped under the blanket of the ionosphere.
In a paper in the online journal Geophysical Research Letters, NASA scientists working on the Goddard Space Flight Center have revealed that they have detected these waves five hundred miles up. It seems these waves are skipping, or leaking, through the boundaries of earth and out into space.
Image of Vector Electric Field Instrument: NASA Goddard Space Flight Center