Imagine admiring the clear sky on a dark winter night and suddenly out of nowhere the sky is filled with a myriad of colours in dynamic patterns that appear as curtains, rays, spirals, or dynamic flickers covering the entire sky.Like a celestial ballet of light dancing across the night sky, with a colour palette of green, blue, and sometimes even pink and violet. I am sure you haven’t seen any thing like this as yet. This is Northern Lights – an atmospheric phenomenon that occurs in high latitude regions of the Northern Hemisphere.
Latitudes are the imaginary lines that circle the earth – for reference the Equator is 0° and as one moves northward the degrees increase to 90° North at the North Pole (in the Arctic Circle) and moving southwards from the Equator the degrees increase to 90° South at the South Pole (in the Antarctic Circle).
This sudden appearance of streaks of light in a dark sky that occurs near the North Pole, also occurs in the Southern Hemisphere , near the South Pole which is on the Antarctic Continent. But since its not possible due to logistical constraints to go to the Antarctic continent to view this, the Lights appearing in the Northern Hemisphere became more popular and got called Northern Lights.
Northern Lights is the popular term used for this phenomena but in scientific language this is called Aurora. And this Aurora occurring in the Northern Hemisphere near the North Pole is called Aurora Borealis and the one in the Southern Hemisphere near the South Pole is called Aurora Australis.
What is this Aurora or Northern Lights ? Why do they occur ? And why only near the Polar Regions ?
The Auroras are in actual fact caused by activity on the surface of the Sun. Solar flares - which are enormous explosions on the suns surface - emit a lot of electrically charged particles into space. These particles travel millions of miles to reach Earth about two days later. Most of these particles are deflected away, but some get captured due the Earth’s magnetic field. These particles then slam into atoms and molecules in the Earth’s atmosphere and essentially heat them up which is called excitation, like heating a gas and making it glow. Different gases give off different colours when they are heated. The same process is also taking place in the atmosphere which has a lot of gases. The two primary gases in the Earth’s atmosphere are nitrogen and oxygen, and these elements give off different colours when they come in contact with the charged particles. The green we see in the aurora is characteristic of oxygen, while hints of purple, blue or pink are caused by nitrogen.
The aurora's characteristic wavy patterns and 'curtains' of light are caused by the lines of force in the Earth’s magnetic field. The Earth's Magnetic field is strongest at the North and South Poles so the charged particles from the Sun get attracted to this magnetic field especially in the polar regions and come accelerating down towards the north and south poles into the atmosphere. This is why aurora activity is concentrated at the magnetic poles.
Which is the best time to view the Northern Lights ?
As explained earlier, the Aurora occurrence is linked to the Solar Storm activity on the Sun’s surface. The frequency of solar storms fluctuates, reaching a peak every 11 years. The last time solar storms peaked was in 2014 and their occurrence is predicted to rise again through to the mid-2020s.
The best time to go is now!
Northern lights activity is peaking in 2024. From now until 2026, the Northern Lights’s activity is expected to reach its highest levels in 11 years. The northern lights can be seen when the sky is clear and dark. Peak time is between 11 p.m. and 2 a.m. Statistically, spring (Feb/ March/April) and autumn (September/October) have the highest level of aurora activity.
Where to go to view the Northern Lights ?
Since the Lights are visible only in the Polar regions, logistically accessible are places close to the North Pole - namely the Scandinavian countries of Finland and Norway as also Russia, Greenland and Iceland. Northern regions in Norway - Tromso, Harstad Narvia - and Finland - north of Rovaniemi are the best areas to view the Northern Lights. Tromso in Norway has an airport and connected by flights to other places in Europe - so it serves as a gateway for most Indians visiting to see the Northern Lights.
Besides the Northern Lights phenomena, Scandinavia has a lot of picture postcard landscapes and you can extend the Northern Lights tour to visit places like Rovaniemi - for unique experiences like the Santa Claus Village or the reindeer/husky dog sleigh ride- Arctic Circle Crossing, picturesque city of Helsinki or even the cities of Oslo and Bergen for a boat ride in the world famous fjords.