Northern lights how does it occur




















Follow the team's Twitter account to see the latest UK alerts. The conditions do still need to be right however. Dark and clear nights, preferably with little light pollution, offer the best chance of seeing the aurora. Any planet with an atmosphere and magnetic field is likely to have aurorae. Scientists have captured incredible images of aurorae on Jupiter, Saturn, Uranus and Neptune. Aurorae on Mars have also been seen, but as the 'red planet' does not have a global magnetic field, aurorae behave differently and appear to be far more widespread.

Solar flares are like enormous explosions on the surface of the Sun in which streams of charged particles are emitted into space. It typically takes two days after the flare is seen on the Sun for the particles to reach Earth.

Upon their arrival, these particles can result in aurora activity. Intense aurora displays are generated following massive explosions on the Sun known as 'coronal mass ejections'. These explosions release clouds of hot plasma containing billions of tons of material travelling at around two million miles per hour.

When the clouds reach the Earth, they interact with the Earth's magnetic field to cause events called geomagnetic storms. The Sun's activity fluctuates, with activity reaching a peak every 11 years.

The last time solar activity peaked was in , and the cycle is now reaching its minimum. However, solar activity is predicted to rise again through to the mids. Regardless of the Sun's activity, aurorae can still occur at any time and observers in high latitudes should always look out for them. Phillip Pullman, His Dark Materials. What is the aurora? Areas that are not subject to 'light pollution' are the best places to watch for the lights. Areas in the north, in smaller communities, tend to be best.

Researchers have also discovered that auroral activity is cyclic, peaking roughly every 11 years. The next peak period is Winter in the north is generally a good season to view lights. The long periods of darkness and the frequency of clear nights provide many good opportunities to watch the auroral displays. Usually the best time of night on clear nights to watch for auroral displays is local midnight adjust for differences caused by daylight savings time.

In Roman myths, Aurora was the goddess of the dawn. In medieval times, the occurrences of auroral displays were seen as harbingers of war or famine. The Maori of New Zealand shared a belief with many northern people of Europe and North America that the lights were reflections from torches or campfires. The Menominee Indians of Wisconsin believed that the lights indicated the location of manabai'wok giants who were the spirits of great hunters and fishermen.

The Inuit of Alaska believed that the lights were the spirits of the animals they hunted: the seals, salmon, deer and beluga whales.

Other aboriginal peoples believed that the lights were the spirits of their people. Northern Lights What are Northern Lights? What causes the Northern Lights? These stories taught people to respect, fear, or worship the lights in the sky. But as our understanding of the solar system and our place within it grew, these stories dissolved into legends and myths.

These particles originate from our star - the sun. The sun is constantly pushing out a stream of electrically charged particles called the solar wind, and this travels out from the sun at between and km per second in all directions.

As the Earth travels around the sun, a small fraction of particles from the solar wind are intercepted by the planet. When these charged particles hit the atoms and molecules high up in our atmosphere, they become excited. This creates two glowing rings of auroral emission around the North and South magnetic poles, known as auroral ovals. As they decay back to their original state, they emit distinctive colours of light.

The realisation of the enormity of the universe washes over you, and you feel small in a good way and full of wonder. These atoms become excited at different levels in the atmosphere. The most common colour seen in the Northern Lights is green.

The red light we sometimes see is also caused by oxygen atoms.



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