The aurora borealis, or polar auroras, are the natural glow in the sky over the North and South polar regions, caused by the interaction between the Earth’s magnetic field and charged particles from the Sun.
In the northern latitudes, these radiations are called northern lights or “aurora borealis”. In southern latitudes, the formation of the southern aurora borealis, called aurora australis, has almost the same characteristics. The term aurora borealis was derived by Galileo in 1619 from the Roman Aurora, the goddess of dawn, and the Greek name for the north wind (Boreas), while the words borealis and australis are derived from the names of the ancient gods of the north wind (Boreas) and south wind (Auster) in Greco-Roman mythology.
Most auroras form in a band known as the “auroral zone”. This band is typically found at latitudes between 3° and 6° and between 10° and 20° from the geomagnetic poles at all local times. The glow is most clearly visible at night in a dark sky. The region currently exhibiting an aurora is called an “auroral oval”, a band displaced by the solar wind towards the night side of the Earth.
Auroras exhibit dynamic patterns of bright lights that appear as curtains, rays, spirals or dynamic pulsations that cover the entire sky. They also occur in scattered patches or arcs toward the pole of the auroral region. They can also occasionally be seen at latitudes below the auroral region, when a geomagnetic storm temporarily expands the auroral oval. Large geomagnetic storms are most common during the peak of the 11-year sunspot cycle or for three years after the peak. Most of the planets in the Solar System, some natural satellites, brown dwarfs and even comets also host auroras.
The colors of auroras vary depending on altitude. At high altitudes, oxygen red predominates, while lower down, the colors change. Auroras are usually red, green or blue. Other shades of red can also be seen, as well as yellow, pink and, in rare cases, orange and gold. In addition, it is possible to see different color mixtures that are unpredictably beautiful.
The oldest depiction of the Aurora may be in Cro-Magnon cave paintings in northern Spain, dating back to 30,000 BC. The oldest known written record of the aurora is in a Chinese legend written around 2600 BC. The first studies on imaging auroras were conducted in 1949 by the University of Saskatchewan using the SCR-270 radar.
The mesmerizingly beautiful auroras have been given different meanings by various peoples around the world. The Cree (kri) people called this strange phenomenon the “Dance of the Spirits”, while Australian Aborigines associated some auroras with fire. According to one source, in the Middle Ages in Europe, auroras were believed to be signs from God.
Aurora Australis can be seen from high southern latitudes in Antarctica, the Southern Cone, South Africa, Australia and, under exceptional conditions, as far north as Uruguay. Aurora Borealis can also be seen from regions or countries around the Arctic, such as Alaska, Canada, Iceland, Greenland, the Faroe Islands, Scandinavia, Scotland and Russia. In rare cases, they can also be seen as far south as the Mediterranean Sea and the southern states of the USA. During the “Carrington Event”, the largest geomagnetic storm ever observed, auroras were seen even in the tropics.
If you want to experience one of the most special moments of your life, you can visit the places where the colorful auroras are best seen. You will definitely never forget these mesmerizing moments!