At nearly light speed, electrons exhibit strange behavior: the mystery has been solved.

In space, supernova explosions, black holes, and other cosmic events can accelerate electrons to nearly the speed of light. This is referred to as relativistic speed. It is believed that the shock waves generated from the transfer of energy between particles during cosmic events act as natural particle accelerators, responsible for accelerating electrons to relativistic speeds. This phenomenon is known as diffusive shock acceleration. However, there is one issue. Before electrons can be accelerated by these shock waves, they must possess a certain amount of energy. The mystery of how electrons acquire this initial energy is termed the electron injection problem. Now, a new study published in the journal Nature Communications elucidates the acceleration of electrons in outer space, as reported by Interesting Engineering.

Scientists have gathered data from NASA spacecraft that provide insights into how solar winds affect and interact with Earth's magnetosphere, revealing the behavior of plasma and magnetic fields in the space around the Earth and the Moon. The phenomenon of the bow shock wave particularly captured the researchers' attention.

This shock wave forms when the fast-moving solar wind suddenly slows down and heats up upon colliding with Earth's magnetosphere.

During this event, electrons in the vicinity of Earth, where the solar wind is previously disturbed by its interaction with the shock wave, gained an unprecedented level of energy: over 500 kiloelectronvolts. Typically, electrons in this region of space have an energy of about 1 kiloelectronvolt.

The findings of the study indicate that high-energy electrons are produced through a combination of various processes, including interactions with plasma waves, transient structures in the region ahead of Earth's bow shock, and the shock wave itself. Together, these processes accelerate electrons and provide them with exceptional energy.

Researchers believe that the acceleration of electrons results from numerous plasma-driven events occurring at different scales. These phenomena energize particles in space. The authors of the study assert that this discovery will aid in understanding electron acceleration not only within the Solar System but also in distant corners of the Universe.