Inexpensive DIY Magnetometer Designs for Formal and Informal Investigations of Geomagnetic Sq Variations and Space Weather Events

Simple magnetometers are the gateway instruments for exploring the geomagnetic field that can be used by hobbyists and teachers alike to monitor and study a variety of space weather phenomena. This article provides designs for four different instruments that can be built for under
${\$}50$
, yet have the sensitivity to detect the diurnal ionospheric Sq variation, and geomagnetic disturbances due to the arrival of solar coronal mass ejections. A comparison of the data from these instruments against contemporaneous data from the Fredericksburg Magnetic Observatory reveal the accuracy of these instruments. Also provided is an example of how these instruments have been used in high school Earth Science and Astronomy classes to improve student learning and scientific curiosity.