Alanna Mitchell's "The Spinning Magnet" is a good popular-level book on the Earth's magnetic field, how it was discovered and investigated, and what's currently

Alanna Mitchell's "The Spinning Magnet" is a good popular-level book on the Earth's magnetic field, how it was discovered and investigated, and what's currently known about it: https://www.indiebound.org/book/9781101985168 https://www.indiebound.org/book/9781101985168 Space-based X-ray telescopes also need to take the South Atlantic Anomaly into account; data taken while the instrument is in the SAA is disregarded.