Scientists at the University of Iowa reported the first detection of cosmic rays from electrons, which were accelerated by shock waves generated by coronal mass ejections on the Sun. The discovery of a previously unknown phenomenon was made with instruments aboard the Voyager 1 and Voyager 2 probes that entered interstellar space. This is reported in an article published in the Astronomical Journal.
It turned out that electrons travel at almost the speed of light, which is about 670 times faster than the shock waves that initially accelerated them. Several days later, following the electronic bursts, the instruments recorded oscillations of plasma waves caused by electrons of lower energies. Finally, a month later, the shock wave itself reached the space probes.
The shockwaves emanated from coronal mass ejections, which are ejections of hot gas and energy that travel from the Sun at more than one million kilometers per hour. However, even at these speeds, it will take more than a year for the shockwaves to reach Voyagers about 20 billion kilometers away.