Wonders of the Aurora Borealis
Tuesday, 06 July 2010
As part of their Gifted and Talented Programme, Sixth Form girls and boys at Bolton School were treated to a fascinating lecture on the aurora borealis (otherwise known as the Northern Lights) by Dr Jim Wild of the University of Lancaster. The presentation, entitled "In Search of the Northern Lights" focused on the physics behind their occurrence and the effect they have had on local art and culture.
Dr Wild spoke of the wonder of the Northern Lights and how it is possible for the night sky to turn from pitch black to swathes of green and red light arcing over you or appearing as a rippling curtain. It is the motion and sweep of the aurora borealis which is amazing and this can not be appreciated on a static image. The dancing lights are visible, to varying degrees, from the ice-caps to the Mediterranean but it is over the Arctic Circle (and Antarctica) where they can be seen most often. In such areas legends abound explaining what they are - anything from the gods playing football to the spirits of young women who died before they got married. Dr Wild explained how the lights have influenced art and culture, citing Philip Pullman's book The Northern Lights as a recent example.
Explaining the physics behind the lights, Dr Wild said the story starts with the sun, which throws out billions of tonnes of matter and light each day, which become a solar wind of electrically charged particles which would hit the earth if it was not for the natural occurring protective magnetic field that enwraps the world. However, these fields are weaker at the very northern and southern tips of the world - these are known as the magnetic poles. Some of the charged particles break through the field at the poles and collide with gaseous particles in the earth's atmosphere - collisions with different gases cause different light formations. It is exactly the same principle of physics used in the creation of neon light.
Dr Wild then joined Poet Laureate, Carol Ann Duffy, who also talked to students, for a buffet lunch with pupils and staff.
Dr Wild graduated with a degree in Physics with Space Science and Technology before completing a doctorate in solar-terrestrial physics at the University of Leicester. He is now a lecturer in the Space Plasma Environment and Radio Science Group in Lancaster University's Department of Communication Systems. His research investigates the physics behind the aurora borealis, the impact of space weather on human technology and the interaction between the Martian atmosphere and the interplanetary environment.