The Northern lights, or Aurora, are beautiful to watch at night. But they can happen during daylight as well. If you want to predict when they will occur, try your hand at building this simple DIY detector.
How to make a Aurora Detector:
To make your own magnetometer all you need is a magnet with a mirror on it, hanging from a thread inside a clear glass bottle (or jar).
You will need to half fill the bottom part of the bottle with sand or small pebbles, this will keep the bottle upright and stop it moving about: Puncture a hole in the centre of the bottle cap (Get an adult to do this for you, if in doubt!) and pass some thread through the cap. The cap will be screwed on later. You need to suspend a small bar magnet (with the thread/string) from the bottle lid. On one end of this magnet attach a small mirror, spend a little time to make sure the magnet/mirror hangs level (Also make sure the magnet and mirror are small enough to pass through the bottle opening). To attach the mirror, glue is ideal, but Blu-tack, or at a snip, toothpaste will do. Make sure that the magnet is able to swing freely when it is inside the bottle, without touching the sides or bottom. You will probably have to adjust the length of the thread. A tip would be to tie the thread around a small used match-stick, so it doesn't slip through the hole in the cap.
The detector is now finished!
You will need to position the detector near to a lamp with clear bulb in it . The light from which will be reflected onto a wall. A tip here is to have the wall no further than one meter away. Shielding of excessive light from the lamp is recommended; so the wall is in shadow. The lamp and detector must NOT be moved. (ever!) If you can see the reflection, attach a white sheet of paper onto the spot on the wall. With a pen, mark the position of the reflection. Take another reading after an hour, and continue to do so. But you may want to take more readings if the reflection moves about a lot. You may notice that the reflection just moves vertically, up and down. Eventually, you may want to replace the paper with graph-paper (that you have marked and numbered), and write the results into a log-book.
Another tip here is to have the detector as far from moving metal objects and electrical wires as possible, as they will affect the results: Roads, railways, lifts and electrical appliances will disturb the magnet.
For those who wish a more advanced detector, you may consider painting the lamp-bulb, with water-base paint, (tip: mixed with soapy water), leaving a small gap for the light to escape and reach the detector. Ideally, a small low-powered laser should replace the lamp.
Ed ~ Feel free to copy & paste or edit this article onto your own site
