Recently, a solar storm hit Earth and tore a crack in the Earth's magnetic field, allowing high-energy solar particles to penetrate deeper into the atmosphere than normal, triggering unusual colors that illuminate the Norwegian night sky with extremely rare pink auroras.
Image courtesy of Markus Varik/Greenlander
The pink aurora appeared near Tromsø, Norway, around 6 p.m. local time on November 3, and lasted for about 2 minutes. Compared to the common green aurora, pink auroras are extremely rare. Cracks in the Earth's magnetosphere also caused intense green auroras throughout the night.
The pink aurora appeared shortly after cracks appeared in the magnetosphere — an invisible magnetosphere that surrounds Earth and is produced by Earth's fluid metal core. A small G-1 solar storm reportedly hit Earth on November 3, and scientists discovered the crack.
Image courtesy of Markus Varik/Greenlander
Image courtesy of Markus Varik/Greenlander
Aurora color and formation
When high-energy charged particles in the solar wind pass through the Earth's magnetosphere, the two collide with each other, forming auroras. Earth's magnetic field protects us from cosmic radiation, but the magnetic field shields at the North and South Poles are weaker, which allows the solar wind to skim through the atmosphere — usually between 100 and 300 kilometers above Earth's surface.
The most common aurora is green because the atmosphere that is normally reachable by the solar wind is rich in oxygen atoms, which emits this green hue when they are excited. However, during this solar storm on November 3, cracks in the Earth's magnetosphere allowed the solar wind to penetrate into the atmosphere 100 kilometers below, where the most abundant gas is nitrogen. So, as the pressure is boosted, most of the charged particles hit the nitrogen atoms, and the aurora produces a neon-like pink glow.
Those who are interested in the aurora must go to the South Pole or the North Pole, and you may want to see the pink aurora with your own eyes!
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