Monday, March 09, 2009

6:44 PM / 0 comments
Heyyo! Today was ok lah. Ate too full so i kinda vomitted during PE. Sianz. But everything else was alright. I really gotta improve on my hcl comprehension! If only it was as easy as LA...

Anw, time for the second part of my geography series. Today, we have *drum rolls*...

Aurora Borealis, also know as the Northern Lights!

Courtesy of: http://onemansblog.com/wp-content/uploads/2007/03/AuroraBorealis.jpg

These aurorae are usually found in the polar regions (in the arctic islands off Canada in this case), in the ionosphere - a layer of the atmosphere filled with ions.

1. Aurorae are formed when charged particles from the Sun (electrons / protons) collide with atoms / molecules in the atmosphere.

2.As they have higher energies than solar wind, the particles are trapped by the Earth's magnetic field.

3. Under a southward magnetic field, the particles charge towards Earth and collide with particles in the upper atmosphere which in turn excites them.

4. The excitation energy is released as light energy, giving us the colours of the aurorae: green or red for atomic oxygen and deep red or bright blue/violet for N2 or nitrogen ions.

Well, complex as it sounds, it's just a mass of collisions among charged particles in the upper atmosphere to release light energy that well-fascinates one with the wonders of geography - its aesthetically pleasing masterpieces.


Aurora borealis levitating over Earth, in its alieny green ensemble.

Courtesy of: http://www.noncombatant.org/trove/aurora-borealis.jpg