First evidence of how auroral beads form

First evidence of how auroral beads form Today’s Video of the Day from NASA Goddard describes a phenomenon in which glowing lights appear across the night sky before a large auroral display.

The lights, which look like a glowing pearl necklace draped from east to west, are referred to as auroral beads.

Scientists have speculated that auroral beads could somehow be connected to disturbances in space or to storms closer to Earth’s atmosphere. 

But now, powerful new computer models and observations from NASA’s Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission have provided the first direct evidence of the events that lead up to the appearance of auroral beads. At least in theory, the fingers may tangle magnetic field lines and cause an explosive event known as magnetic reconnection, which is well known to create full-scale substorms and auroras that fill the nightside sky, experts said. First evidence of how auroral beads form Auroras are created when charged particles from the Sun are trapped in Earth’s magnetic environment—the magnetosphere—and are funneled into Earth’s upper atmosphere, where collisions produce the glow in hydrogen, oxygen, and nitrogen atoms and molecules.

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By Chrissy Sexton, Earth.com Staff Writer

Video Credit: NASA Goddard