For many centuries, aurora has been the mystery of the sky that people guess and explore. Once upon a time, the Eskimos thought it was the torch that the ghosts and gods guided the souls to heaven. In the 13th century, people thought it was the light reflected by the Greenland Ice Sheet. In the 17th century, it was called the Northern Lights – the Arctic dawn (the same light seen in the Antarctic is called the South Pole).
With the advancement of technology, the mystery of Aurora is becoming more and more known to us. Originally, this beautiful scenery is a work performed by the Sun and the atmosphere. Among the energies created by the sun, such as light and heat, one type of energy is called the “solar wind.” The solar wind is a charged particle ejected by the sun. It is a powerful charged subatomic particle stream that covers the earth and is in a plasma state. The solar wind travels around above the earth, striking the Earth’s magnetic field at a speed of about 400 kilometers per second. The earth’s magnetic field is shaped like a funnel, and the tip is facing the north and south magnetic poles of the earth, so the charged particles from the sun along the earth’s magnetic field settles and enters the polar regions of the earth. The high-level atmosphere of the two poles will shine when they are bombarded by the solar wind, forming an aurora. The Antarctic light formed in the Antarctic region and the Northern Lights formed in the Arctic region.
Aurora is a process of large-scale discharge around the Earth. The charged particles from the sun reach the Earth, and the Earth’s magnetic field forces part of it to concentrate along the field line to the north and south poles. When they enter the upper atmosphere of the polar earth, they collide with the atoms and molecules in the atmosphere and excite, generating light and forming an aurora. Frequently, in two ring-shaped zones around 67 degrees north-south latitude, Fairbanks in Alaska has more than 200 days of aurora in a year, so it is called the “Northern Lights Capital.” So the aurora can only be seen in the north and south poles of the earth. When the solar wind is strong, there is a lot of energy that can’t be consumed, so the aurora is formed at the ionosphere.