The Northern Lights: How Do They Light Up the Sky?

Do you wonder what those magnificent colors of light are when you look up in the sky? They are The Northern Lights, also known as Aurora Borealis, can only be observed in the proximity of the earth north of the equator (Northern Hemisphere).They are usually visible from March-April and September-October. Autumn is the very best time to observe them. Prominent in Alaska and Canada, they can also be seen in other parts of the Northern Hemisphere. Wikipedia.com defines an aurora as an electrostatic phenomenon characterized by a bright glow, and caused by the collision of charged particles in the magnetosphere with atoms in the earth's upper atmosphere. The specific magnetosphere in this case, is the magnetic field around the earth.

Northern Lights originate from the sun. The sun has a coronal mass ejection, which are explosions and flares that erupt into space. These ejections travel through space to the earth's atmosphere. When they hit the magnetosphere of the earth, they are captured by it, and travel to the two geomagnetic (south and north) poles. When the particles hit the magnetic field, (a collision of the solar particles and gases from the earth) a proton is made. A proton is a light particle. Many collisions happen to have the effect of lights across the sky. Those lights are the Southern and Northern Lights. The Southern Lights are only visible in the Southern Hemisphere. They both can be seen without the use of a telescope. The latitude and longitude, and specific gaseous in the atmosphere determine what color the aurora will illuminate. For example: Nitrogen will show a red light and Oxygen will show green.

To observe them will take some luck and immense patience. Three days is the best advance notice that can be achieved right now. A magnetometer is utilized to measure the interaction between charged particles from the sun and the magnetosphere, (as defined by Wikipedia.com.) The chances of seeing the aurora are better when the interaction is high. The website http://www.spacew.com/aurora/index.html can help with monitoring the aurora in real time. The best time for observing them is between 10 pm and midnight.

To observe them, find a place entirely dark outside at night (10pm to 12am being the best view time), away from city lights. A telescope can be used but is not necessary. Making sure you have checked the website above for location, now is the time for patience. It will pay off when you see the brilliance of the colors.

In Nordic mythology, it was believed the shields of the Valkyrie's (warriors for Odin) gave off bright lights when they went into battle. The bright lights were The Northern Lights. Native Americans believed "God himself lighted up the dark and cold parts of the world." Others believed they were an omen of war.

The first written reference to the aurora goes back to the Old Testament. However, the name Aurora Borealis is said to come from the Italian scientist Galileo Galilei. It means red dawn of the north in Latin.

The aurora continues to be researched and studied by scientists all over the world.

Sources:
Wikepedia.com
Northern-lights.no/
http://www.pbase.com/ivarg/aurora_borealis