The Northern Lights are generated by Electrons ‘surfing’ on Alfven waves?

The Northern Lights are generated by Electrons ‘surfing’ on Alfven waves?

The Northern Lights are generated by Electrons ‘surfing’ on Alfven waves?

Humanity has always been fascinated by the magnificence of the auroras shining brightly.

Now, scientists have demonstrated how electrons associated with auroras are accelerated toward Earth, where they collide with molecules in the upper atmosphere.

These collisions lead to the emission of auroras. The new study reproduced the spatial conditions above the aurora in the laboratory.

It shows that Alfvén waves, initiated by storms in Earth’s magnetic field, can accelerate electrons, resulting in the bright glow of auroras.

These results unequivocally confirm this previously unproven hypothesis.

New experiments reveal the source of the Northern Lights. Scientists have demonstrated Alvin waves that accelerate electrons under conditions similar to those in Earth’s magnetosphere.

Ionized charged particles, or plasma, are one of four substances (along with solids, liquids, and gases) found in the magnetosphere that surrounds Earth.

Plasma has properties similar to liquids and gases, but they also have magnetic and electric fields. Hannes-Alvin predicted in 1942 that plasma could support waves. These waves are now known as Alfvén waves.

A theory that has previously been supported is that scientists often find powerful electromagnetic waves, called Alvin waves, moving toward Earth on auroras.

According to this theory, Alfvén waves accelerate electrons toward Earth, causing them to precipitate and create auroras.

Although space-based measurements provide strong support for this theory, the limitations of these measurements prevent a definitive test.

To overcome these limitations, the researchers conducted laboratory experiments at the Large Plasma Device (LAPD) at the University of California, Los Angeles (UCLA) Basic Plasma Science Facility, a state co-supported by the Department of Energy and the National Science Foundation.

Cooperative Research Facility. In a laboratory experiment that reproduced conditions in Earth’s magnetosphere, the team fired an Alvin wave into the LAPD chamber and then measured electrons accelerated by the Alvin wave’s electric field.

The measurements showed that these special electrons were resonantly accelerated by the wave’s electric field, similar to a surfer grabbing a wave and being continuously accelerated by the wave.

The transfer of the wave’s energy to the accelerated electrons is known as Landau damping.

The team combined measurements of the wave’s electric field and electrons to produce the unique signature of Landau-damped electron acceleration.

Through simulations and modeling, they showed that the experimentally measured acceleration characteristics were consistent with the predicted Landau damping characteristics.

The agreement between experiments, simulations, and modeling provides the first direct test that Alvin waves can generate accelerated electrons that cause auroras.