Electrons “surf” in space to create the Northern Lights, new study finds
Physicists are excited to share definitive evidence that the northern Lights – this colorful glow from the sky, also known as the Northern Lights, is the result of gnarled electrons “surfing” through the cosmos on powerful festive waves. The team’s results were published on June 7 in the scientific journal Totally Tubular Nature Communication.
Scientists have known for some time that auroras occur when energized particles from the sun fly into space and crash into Earthof the magnetosphere. These energized particles ride our planet magnetic field in the upper atmosphere, where they collide with oxygen and nitrogen molecules, releasing dazzling colored light in the process.
But there is still a big lingering question about the aurora process: How do these solar particles acquire enough speed and energy to crash into Earth’s atmosphere with such force?
One popular explanation involves Alfven waves – powerful geomagnetic waves that propagate through plasma, a charged gas that makes up solar winds.
Related: Aurora photos: northern lights dazzling in night sky images
These waves can pick up stray electrons in plasma and accelerate them to extremely high speeds (over 45 million mph or 72 million km / h) without deviating from their path. Space instruments detected Alfven waves moving towards Earth above the aurora, but scientists had no definitive way to prove that these waves accelerate electrons – until now.
In the new study, the researchers used an instrument called the Large Plasma Device (LPD) – a 20-meter-long vacuum chamber at UCLA capable of containing a magnetic field – to recreate the Alfven waves under similar conditions. to those in solar winds. The team measured the speed of electrons moving through the plasma chamber and found that a small number of electrons were indeed accelerated to high speeds by the waves.
The effect on electrons was “similar to a surfer catching a wave and being continuously accelerated as the surfer moves with the wave,” study co-author Greg Howes, associate professor of physics at the University of the Iowa, said in a press release.
The team’s experimental results aligned perfectly with mathematical models and computer simulations of this wave surfing effect, providing the first “definitive” evidence that Alfven waves fuel the Northern Lights, the researchers said. Cowabunga!
Originally posted on Live Science.