Photo reference
An aurora is a shimmering display of natural light in the sky. Lights in the shades of blue, red, pink, yellow, green, and orange move and shape-change subtly, like softly billowing curtains. Only at night are auroras visible, and they typically only emerge in the lower polar areas. Auroras, often known as the polar lights, are most frequently observed in high-latitude locations (around the Arctic and Antarctic).
Why do they occur?
The solar wind's effects on the magnetosphere lead to auroral phenomena.
We receive a lot of additional energy and tiny particles from the Sun in addition to heat and light. We are mostly shielded from energy and particles by the protective magnetic field that surrounds Earth, and we are hardly aware of it.
However, the Sun doesn't always send the same quantity of energy.
Both solar storms and a continuous stream of solar wind exist.
The Sun releases a large bubble of electrified gas—known as a coronal mass ejection—during a specific type of solar storm that may move through space quickly.
Coronal holes and coronal mass ejections accelerate the solar wind, which causes significant disruptions.
The paths of charged particles in the magnetospheric plasma are changed by these disruptions. These particles (
primarily electrons and protons) precipitate into the high atmosphere (thermosphere/exosphere).
As a result, air elements are ionized, releasing light with a range of colors and complexity (electrons and protons collide with the gasses)
The auroras appear to move or "dance" in the sky as billions of flashes happen one after another in succession.
The amount of acceleration applied to the precipitating particles affects how the aurora, which occurs in bands around both polar regions, takes shape.
Sometimes magnetic storms and active auroras can disrupt communication. Radio and radar signals can be interfered with by them. Even communication satellites can be made obsolete by powerful magnetic storms.
Colors of Auroras
Depending on the type of atoms involved and the altitude, auroras have a variety of hues. High in the atmosphere, ions can combine with oxygen atoms to produce a red light. The most common aurora, a green-yellow color, happens when ions strike oxygen at lower altitudes, making this one unique. Ions striking nitrogen atoms result in the reddish and blue light that is frequently visible in the bottom fringes of auroras. Though we seldom have the ability to see this region of the electromagnetic spectrum with our eyes, ions impacting hydrogen and helium atoms can result in blue and purple auroras.
Photorefrence- https://www.theguardian.com/science/blog/2017/feb/02/why-the-rare-blood-aurora-inspires-awe-and-foreboding
Where does the name ‘Aurora' originate from?
The name of the Roman dawn goddess Aurora, who traveled from east to west proclaiming the rising of the sun, is where the term "aurora" originates. The dawn was symbolically referred to as Eos by ancient Greek poets, who frequently spoke of its display of hues against an otherwise gloomy sky (e.g., "rosy-fingered dawn").
The first studies of Auroras
A Cro-Magnon cave artwork from 30,000 BC may have been the first depiction of the aurora. Ancient Roman and Greek astronomers frequently studied the aurora borealis, or northern lights, though it was only later that the astronomer and physicist Galileo Galilei gave this phenomena the name Aurora Borealis towards the beginning of the 17th century.
Mythology of Northern Lights
Nowadays, we know of the studies conducted on Northern Lights, but how did our ancestors perceive this phenomenon?
Greece and Rome
Sightings far south are nearly unheard of, therefore the ancient Greeks must have witnessed some extraordinarily intense solar activity.
The sun and moon, Helios and Seline, were believed to be siblings, and the Greeks believed that Aurora raced across the early morning sky in her multicolored chariot to warn her siblings that a new day had begun.
The dawn was also symbolized by the Northern Lights for the Romans, who thought they were Aurora, the morning goddess.
Southern Europe
The Northern Lights infrequently appear over Southern Europe, and when they do, they often manifest as crimson Auroras in the night sky due to extremely intense solar activity. Unsurprisingly, when they did occur on rare instances, they generated quite a commotion and were frightening.
For instance, the impoverished inhabitants of France and Italy thought the lights were a dreadful omen signaling the beginning of anything from war to the plague and death. The sky is reported to have turned scarlet in Scotland and England just a few weeks before the French Revolution, and this is now thought to have been a warning of impending upheaval in their Gallic neighbor state.
Asia
Due to the rarity of auroral sightings in China and the likelihood that they were triggered by a large solar event, it is not unexpected that the ancient Chinese were astounded by the lights that sometimes lit up their night sky.
Many of the early Chinese dragon legends are said to have originated as a result of the Northern Lights. The lights, according to popular belief, were thought to be the result of a supernatural conflict between good and bad dragons that spewed fire over the heavens.
In Japanese tradition, it is said that a child born during the Northern Lights would be endowed with attractiveness, intelligence, and luck. The Aurora is, in fact, a source of great attraction throughout South East Asia.
North America
Human settlements were far less dense centuries ago, and humans lived in much smaller, more isolated villages with very little interaction with other tribes. As a result, several tribes or groups of people in North America developed their own mythology about the Aurora Borealis. The following are only a handful of the numerous and diverse ideas that our forefathers in North America held.
The Cree Indians believed that the Aurora represented the spirits of the deceased who were separated from their loved ones in the sky but still a part of life's cycle. The Cree people thought that the lights were the ghosts of these deceased friends and family attempting to contact their loved ones who remained on earth.
According to the Algonquin interpretation of the Aurora, it was produced by light from a fire that their creator, Nanahbozho, had lit. They perceived the fire as Nanahbozho's means of showing his people that he was thinking of them and keeping an eye on them.
The very creative Makah Indians in Washington State believed the lights were fires in the north started by a tribe of dwarfs who used it to cook whale fat. The Mandan people of North Dakota likewise placed considerable emphasis on fire and cooking. They said that the lights were once again flames over which powerful warriors were boiling their victims in enormous cooking pots.
Northern Scandinavia, Iceland and Greenland
As long as the expecting mother didn't stare at the Aurora whilst giving birth, the lights would ease the pain of delivery according to our Icelandic ancestors.
In Greenland, the lights were likewise connected to childbirth, but unhappily, it was thought that they were the spirits of newborns who had died during pregnancy or delivery.
One of my all-time favorite tales is from Finland, where it was believed that the Aurora was the result of a firefox running across the snow so swiftly that his tail produced sparks to shoot into the night sky, producing the light show. In fact, the phrase "revontulet" for the Northern Lights in Finnish clearly translates to "fire-fox."
The Aurora was frequently interpreted in Sweden as a sign of good fortune. A large portion of our Swedish ancestors thought that the northern lights were a gift from kind gods who were offering warmth and light in the shape of a volcano. The lights were seen as a sign of abundant harvests in the next year by the Swedish agricultural community and were thought to be the light reflection from vast shoals of herring elsewhere in the nation.
Norse mythology features many representations of the Northern Lights. According to a mythology, the lights were made up of the shields and armor of the Valkyrie, female warriors who had the power to decide who would fall in battle and who would survive to fight another day. Norse mythology tended to place a lot of emphasis on dying in combat, and the Aurora was also thought to be "Bifrost Bridge," a blazing and pulsing bridge that guided warriors who died in battle to their last resting place in Valhalla.
Estonia
Finally, Estonia. The lights, according to the Estonians, were magnificent horse-drawn carriages transporting celestial guests to a grand celestial wedding.
Where else can Auroras be found?
Auroras are not only a phenomenon that occurs on Earth. Auroras are presumably present on planets that have magnetic fields and atmospheres.
Amazing auroras have been observed on Jupiter and Saturn.
Auroras may be seen on the majority of the planets in the Solar System, a few natural satellites and even comets.
Jupiter's aurora. (Credit: NASA, ESA, and J. Nichols (University of Leicester))
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