Periodic table of (weather) elements: Nitrogen and the northern lights
Wednesday, May 21, 2014, 3:29 PM - Though most commonly green, northern lights come in a variety of colours -- including blue, yellow, purple and red.
WHAT CAUSES THE NORTHERN LIGHTS?
Northern lights -- or aurora borealis -- occur when solar particles collide with the Earth's atmosphere. Their colour variety results from the presence of different types of gas particles, and the colour of an aurora is dependent on the wavelength of light that's emitted.
Two of the most common elements in the Earth's atmosphere -- oxygen and nitrogen -- create different types of northern lights.
Oxygen is responsible for green and yellowish-green auroras.
Blue, purple and reddish purple auroras are rare in comparison. They're created with the help of nitrogen.
WHAT IS NITROGEN?
Nitrogen plays an important role in the life of plants and animals on Earth.
We usually refer to the air we breathe as "oxygen", but nitrogen is another common element in our air, making up about 80 percent of our planet's atmosphere.
It was first isolated by Scottish chemist Daniel Rutherford in 1772 and given the name "nitrogen" by French chemist Jean-Antoine Chaptal in 1790.
Nitrogen is used to make fertilizers, nitric acid and explosives.
It is also used in the production of stainless steel and in incandescent light bulbs.