The Northern Lights, Aurora borealis
August 21st – April 21st
When in Lapland you have a good chance of seeing the Northern Lights, the Aurora Borealis. The deep green and yellow colors, sometimes streaked with bands of red, are one of the most astonishing natural phenomena it is possible to witness. You have the best chances to see the Northern Lights if you choose accommodation far away from towns and skiing centers or if you book a guided tour, because the artificial light disturbs watching them.
The physics behind the auroras
The typical “northern lights,” or aurora borealis, are caused by collisions between fast-moving electrons and the oxygen and nitrogen in Earth’s upper atmosphere. The electrons – which come from the magnetosphere, the region of space controlled by Earth’s magnetic field – transfer energy to the oxygen and nitrogen gases, making them “excited”. As they “calm down” and return to their normal state, they emit photons, small bursts of energy in the form of light.
When a large number of these collisions occur, the oxygen and nitrogen can emit enough light for the eye to detect. This ghostly light will produce the dance of colors in the night sky we call the aurora. Most of the light comes from altitudes between 60 and 200 miles. Since the aurora is much dimmer than sunlight, it cannot be seen from the ground in the daytime.
Why the different colors?
The color of the aurora depends on which gas – oxygen or nitrogen – is being excited by the electrons, and on how excited it becomes. Oxygen emits either a greenish-yellow light (the most familiar color of the aurora) or a red light; nitrogen generally gives off a blue light. The blending of these colors can also produce purples, pinks and white. The oxygen and nitrogen also emit ultraviolet light, which can be detected by special cameras on satellites but not by the human eye.
Why the different shapes?
Scientists are still trying to answer this question. The shape of the aurora depends on the source of the electrons in the magnetosphere and on the processes that cause the electrons to precipitate into the atmosphere. Dramatically different shapes can be seen over the course of a single night.
Where can the aurora be seen?
Auroras usually occur in ring-shaped areas circling the magnetic poles of the Earth. The rings expand and contract with the level of auroral activity. The best places to see auroras are in northern Scandinavia, northern Russia, mid Canada and Alaska. An entire ring, called the auroral oval, can only be seen from outer space. Good view to north on an absolitely dark hill or mountain is the best guarantee to see this phenomenon, from the Arctic Circle to the North Pole. In Finnish Lapland we all see the same Northern Lights so there is not much difference where you stay. Good view to northern horizon is important, mountain or large lake and absolute darkness. It is better choose us Aurora experts and see the real lights!
Can you hear the aurora?
Observers have speculated about this for hundreds of years, noting that they have heard crackling, swishing and hissing sounds. But the air where auroras are formed is too thin to even conduct sound, and scientists have been unable to detect any.
Why is the aurora important?
The aurora is the only visible evidence that the Sun and the Earth are a system connected by more than sunlight. The Sun’s corona continuously emits a solar wind, a stream of electrically charged particles (mostly protons and electrons) flowing out in all directions. These particles interact with Earth’s magnetic field (right side of figure), which reaches far into space. Most of the particles from the Sun are deflected by the magnetic field, creating a huge cavity in the solar wind. This cavity is called the magnetosphere, and it stretches about 60,000 kilometers on the day side (toward the Sun) and several hundred thousand kilometers in a long tail on the night side.
Under certain conditions more of the energy carried by the solar wind can enter the magnetosphere. Here the energy is converted into electric currents and electromagnetic energy and temporarily stored.
This higher energy state of the magnetosphere is unstable and the energy of the currents can be released suddenly. Some of this energy accelerates electrons in the magnetosphere and causes them to spiral down the Earth’s magnetic field into the atmosphere, where they produce the aurora. By studying the patterns of auroral light, scientist can obtain a picture of what is happening in the huge magnetosphere.
Real-time Data
Check the real-time data here: LINK
Aurora hunting
Lapland Welcome has arranged Aurora hunting at the Arctic Circle and further north for years. The likelihood to see Northern Lights – Aurora Borealis is about 90% in clear nights and on organized trips. The weather on the mountains (called in Lapland “fells”) is unpredictable, you never know which night is the best night and the weather often changes several times during the trip. Only one thing is sure – if you don’t try you don’t see the lights! On guided tour the chances to see the Northern Lights are the best. The best place is an absolutely dark mountain with a good view to north and comfortable shelter to keep you warm. Lapland Welcome offers Northern Lights trips every evening from August 21st till April 21st. Daily trips from Rovaniemi, Kemi, Katkavaara and Ivalo-Saariselka and round tours all over Lapland and northern Scandinavia as well as private tours are organized. Book online or ask an offer!
Glass igloos?
Glass igloos for tourists have been built in several destinations in Finnish Lapland. It is a nice experience to sleep in a glass igloo and watch the sky above from your bed but … to see the Aurora you would need good micro climate, good view to the northern horizon as most of the lights are next to the horizon and a guide supporting and telling what is visible. The best chances you have outside of the glass igloos if they are located well, usually not. The location is everything. Igloos on mountains are rare. We recommend investing better on our guided tours.
Welcome to our guided tours or book from us the best accommodation for viewing Auroras – we have the knowledge!
-text by Lapland Welcome Ltd, Northern Lights club and Sodankylä Geophysical Observatory-
