The color of the aurora depends on which gas – oxygen or nitrogen – is being excited by the electrons, and on how excited it becomes.
Since the aurora is much dimmer than sunlight, it cannot be seen from the ground in the daytime. Most of the light comes from altitudes between 60 and 200 miles. This ghostly light will produce the dance of colors in the night sky we call the aurora. When a large number of these collisions occur, the oxygen and nitrogen can emit enough light for the eye to detect. As they “calm down” and return to their normal state, they emit photons, small bursts of energy in the form of light. 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”. 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. 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 deep green and yellow colors, sometimes streaked with bands of red, are one of the most astonishing natural phenomena it is possible to witness. When in Lapland you have a good chance of seeing the Northern Lights, the Aurora Borealis.
The Northern Lights, Aurora borealis August 21st – April 21st
0 kommentar(er)
