I love it when people use humble PVC as a project enclosure. In this case, Alex Avtanski of San Jose, CA, built this DIY Magnetometer to detect and measure magnetic storms.

The activity of the Sun varies on a cycle with a period of approximately 11 years. Periods of low solar activity are followed by a few years of sharply increased number of solar spots, flares, and coronal mass ejections (CMEs), disrupting Earth’s magnetic field and causing magnetic storms. With the next Solar cycle maximum approaching I wanted to get on the fun too, so I set to build my own device for detecting and recording those magnetic storms, a.k.a. a magnetometer.
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My magnetometer is of a torsion design. Torsion magnetometers work as follows: A magnet, attached to a mirror, is suspended from a thread. A laser beam is reflected from the mirror and falls on a detector. Changes in the Earth’s magnetic field turn the magnet and the attached mirror, twisting the torsion thread. The reflected beam changes its position on the sensor, the changes are recorded and plotted on a chart.