Demystifying Science: What is the Whistler-mode Chorus?

These are waves in space created by fluctuating electric and magnetic fields. The waves have characteristic rising tones — reminiscent of the sounds of chirping birds — and are able to efficiently accelerate electrons. Scientists have long known that solar-energised particles trapped around the planet are sometimes scattered into the earth’s upper atmosphere where they can contribute to beautiful auroral displays. Yet for decades, no one has known exactly what is responsible for hurling these energetic electrons on their way. Recently, two spacecraft found themselves at just the right places at the right time to witness, first hand, both the impulsive electron loss and its cause. New research using data from NASA’s Van Allen Probes Mission and FIREBIRD [Focused Investigations of Relativistic Electron Burst Intensity, Range, and Dynamics] II CubeSat has shown that a common plasma wave in space is likely to be responsible for the impulsive loss of high-energy electrons into the earth’s atmosphere. — Science Daily