The Earth’s magnetic field remains more or less of a mystery to physicists and astronomers. While it’s known that the geomagnetic field shields the Earth from the Sun’s deadly cosmic radiation, there are still higher mysteries afoot with the protective magnetic bubble surrounding the Earth.
Earlier this year, satellites detected that the Earth’s geomagnetic field was weakening due to unexplained causes; soon after it was discovered there was a massive crack in the magnetic field that left physicists baffled. It’s even speculated that the Earth once had many more than two magnetic poles due to the evolution of the spinning molten metal core deep below Earth’s crust.
Now, scientists studying the Earth’s magnetosphere have detected a new mysterious phenomenon just beyond the magnetic field. According to a NASA press release, astronomers have observed mysterious high-energy electrons flying through space at speeds approaching the speed of light. David Sibeck, co-author and THEMIS project scientist at NASA Goddard, claims that these electrons essentially defy our current models of physics:
This is a puzzling case because we’re seeing energetic electrons where we don’t think they should be, and no model fits them. There is a gap in our knowledge, something basic is missing.
The electrons are thought to originate in what’s known as the “foreshock,” the region of space just beyond the Earth’s radiation-shielding magnetic field. According to the researchers’ published data in Physical Review Letters, the speed to which these electrons are being accelerated by the Earth’s foreshock region could be the tip of the iceberg for a host of new physics discoveries:
[…] no known shock acceleration mechanism can energize thermal electrons up to relativistic energies. The discovery of relativistic electrons associated with foreshock structures commonly generated in astrophysical shocks could provide a new paradigm for electron injections and acceleration in collisionless plasmas.
This mysterious electron phenomenon was discovered by NASA scientists working on the THEMIS mission, whose mission statement is to “resolve one of the oldest mysteries in space physics” by finding an explanation for auroras in Earth’s magnetic field.