At http://phys.org/print356081070.html … the ESA Cluster satellites (a group of four satellites closely orbiting on a near trajectory, have observed noise waves inside the Earth's magnetosphere. In a region of space about 12,000 mile upwards the four satellites have seen a stack of 13 space plasma stripes … see image above. Each stripe appeared to be a multiple or harmonic of a proton gyrofrequency – the frequency at which protons gyrate around Earth's magnetic field line. The structure appears to be very persistent, highly coherent in space, and remarkably well organised – which was apparently a surprose.
The paper is in Nature Communications, July 14th (2015)