Teacher's Guide for:

Arctic Light

“Arctic Light” is a 35mm, two-story-tall film shown at the Staerkel Planetarium.  The film was entirely shot in Norway and made its Western Hemisphere premier at the Staerkel Planetarium in 1989. 

The film examines different kinds of light, including artificial light (made by humans), the “Midnight Sun” and the Northern Lights or Aurora Borealis.

The “Midnight Sun” is a strange occurrence that can be found above the Arctic Circle or 66.5 degrees north latitude.  This works in the southern hemisphere at more than 66.5 degrees south latitude as well.   In the summer months, the Sun ventures low in the sky but never sets!!   If time permits, this is shown on the planetarium dome using the Zeiss star projector.   At the north pole, there is six months of daylight and six months of darkness.   This results from the Earth’s 23.5 degree axial tilt. 

The highlight of the film is the fascinating time-lapsed photography of the Northern Lights.  The Northern Lights are actually the Earth’s air glowing.   Particles (parts of atoms) from the Sun bathe the inner solar system, though we are protected by the Earth’s magnetic field; the same thing that makes our compass needles point north.  Though we can’t see the field visually, we can detect it.   From the side it looks like an apple that’s been cut in half.   On the Sun side, particles from the Sun compress the field.   On the nighttime side, the field stretches out.  The field approaches the Earth’s surface at the poles.  Particles are trapped in the Earth’s magnetic field, spiraling around the magnetic field lines.   You can demonstrate this by using a bar magnet and iron filings.  As the particles collide with the air molecules, the energized air molecules emit light.  This is similar to a fluorescent light fixture in your school. 

The Northern Lights or Aurora are very unpredictable, but more common during sunspot maximum, which occurs every 11 years or so.  A mild sunspot maximum occurred in the spring of 2000.  If we observe large “coronal mass ejections” from the Sun, there’s a good chance we will see something.   But how far south the Northern Lights will appear is up for grabs.  See the web sites below for predictions:

For more information:
Space Environment Center:  http://www.sel.noaa.gov/
The SOHO satellite:  http://sohowww.nascom.nasa.gov/
Space weather:  http://www.spaceweather.com
The Sunspot cycle:  http://www.sunspotcycle.com/
Earth camera:  http://solar.spacew.com/www/aurora.html