University of Wisconsin | 2018 Jan 30
[img3="Top: Electron movement in solar wind parallels magnetic field direction. Bottom: After magnetic reconnection, the electrons lose their alignment with Earth’s magnetic field. Credit: UW-Madison"]https://news.wisc.edu/content/uploads/2 ... 00x452.jpg[/img3][hr][/hr]Space physicists at University of Wisconsin–Madison have just released unprecedented detail on a bizarre phenomenon that powers the northern lights, solar flares and coronal mass ejections (the biggest explosions in our solar system).
The data on so-called “magnetic reconnection” came from a quartet of new spacecraft that measure radiation and magnetic fields in high Earth orbit.
“We’re looking at the best picture yet of magnetic reconnection in space,” says Jan Egedal, a professor of physics and senior author of a study in Physical Review Letters. Magnetic reconnection is difficult to describe, but it can be loosely defined as the merger of magnetic fields that releases an astonishing amount of energy.
Magnetic reconnection remains mysterious, especially since it “breaks the standard law” governing charged particles, or plasma, Egedal says.
Egedal and colleagues studied recordings from Oct. 15, 2016, when the Magnetosphere Multiscale satellite passed through the point where the solar wind meets Earth’s magnetic field. “Our data clearly show that electrons suddenly cease to follow magnetic fields and zoom off in another direction, corkscrewing and turning. That begs for explanation,” Egedal says. ...
Spacecraft Observations of Oblique Electron Beams Breaking the Frozen-In Law During Asymmetric Reconnection - J. Egedal et al
- Physical Review Letters 120(05):5101 (02 Feb 2018) DOI: 10.1103/PhysRevLett.120.055101