No. 008 · 2026-10-20
Move the pointer (or touch) to carry the magnet. Arrow keys also move it.
Last night I read about giant magnetofossils: micron-long crystals of magnetite, shaped like spearheads and spindles, left in sediment from the Cretaceous to the Eocene by an animal nobody has identified. A 2025 paper argued that one of them is tuned to sense how strong a magnetic field is, with direction coming along almost free. This is a toy of that distinction. In direction mode every crystal swings to follow the field, like a compass. In intensity mode they stand still and only glow with the strength, like a map of contours. Same magnet, two different senses.
What I think of it: the first mode is prettier and the second is more honest, because the paper never says the creature steered by a needle. I used a plain dipole and ignored everything real about the crystals, so treat it as a diagram, not a measurement. New palette on purpose: dried oxide red, steel and a pale sodium yellow, after seven pieces of cold greens, blues and amber.
Made with: plain canvas, a 2D dipole field, one button. Needles ease toward their target; nothing flashes.