Electrons Help To Create Northern Lights, NASA

Scientists have always been awed at the colorful auroras also called the Northern Lights. Seen most often in the sky over the North Pole, these beautiful colors are displayed after a number of electrically charged particles, or electrons, "charge down" into the atmosphere and collide with air particles in the magnetic field.

Most people believe that auroras are a winter phenomenon, because the skies are very dark in this area around North Pole. However, you can see them all year round.

People in Northern Europe, Scandinavia, and Iceland get a grand Northern Lights show when a powerful solar storm "supercharged" the auroras in these regions, and lit up the evening sky with bright and beautiful colours.

"Using two satellites, a ground-based array of all-sky cameras, and some spectacular aurora borealis, NASA scientists compared videos of pulsating auroras," according to natureworldnews.

Some kinds of aurora are manifested as bright patches that keep flickering on and off. A drop in the low-energy electrons has a major role to play in the fast changing shape and structure of the auroras.

"Without the combination of ground and satellite measurements, we would not have been able to confirm that these events are connected," said Marilia Samara, a space physicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and lead author.

Other active auroras form elongated arcs in the sky. Though all of them are created from energetic particles, their sources differ, according to the sciencedaily.

"The hemispheres are magnetically connected, meaning that any time there is pulsating aurora near the north pole, there is also pulsating aurora near the south pole," Robert Michell, a space physicist at NASA Goddard and one of the study's authors, said in a statement. "Electrons are constantly pinging back and forth along this magnetic field line during an aurora event."

These are low-energy secondary electrons, or slower particles. There are a lot of changes in the structure or shape of an aurora when a few of these pass along magnetic field lines.

"It turns out that secondary electrons could very well be a big piece of the puzzle to how, why, and when the energy that creates auroras is transferred to the upper atmosphere," Samara added in the release. "We need targeted observations to figure out exactly how to incorporate these low-energy secondary electrons into our models. But it seems clear that they may very well end up playing a more important role than previously thought."

Their findings were recently published in the Journal of Geophysical Research.