What Causes the Northern Lights?

"The aurora borealis is usually visible only way up north, but over the past 18 months, shimmering curtains of pink and green light have filled night skies across much of North America, at times offering dazzling displays as far south as Texas and Hawaii. These widespread light shows have been caused by especially strong blasts of solar wind -electrically charged particles shot out from the sun at incredible speeds."

"You might think of the sun as a great ball of fire-but it's not. (Fire is a chemical reaction between oxygen and carbon.) What the sun is, really, is a giant nuclear fusion reactor. In the core, protons are smashed together under extreme pressure. These protons stick together to create the nucleus of a helium atom, with two protons and two neutrons. (Two of the protons decay into neutrons)."

"But wait! The helium nucleus has less mass than the four protons we started with. That mass isn't lost-it's turned into energy, according to Einstein's famous equation E = mc2, where E is energy, m is mass, and c is the speed of light. That last number is huge-light travels at 300,000 kilometers per second, and it's hugeness is squared-which means that even a tiny loss of mass creates A LOT of energy."

Shimmering auroras have appeared across much of North America over the past 18 months, reaching unusually southern latitudes such as Texas and Hawaii. These displays result from strong blasts of solar wind—electrically charged particles expelled from the sun at high speeds—driven by the sun reaching the peak of its roughly 11-year solar cycle. The peak increases the frequency and intensity of solar storms, and stronger-than-normal storms and widespread auroras are expected to continue into 2026. Space weather describes the interaction between the sun and Earth and can have both spectacular visual effects and dangerous consequences. The sun generates its energy through nuclear fusion, where proton fusion into helium converts a small amount of mass into enormous energy via E = mc2, producing the extreme heat of the solar core.

Read at WIRED