
Photo of a grubby optical table with a piece of chipboard on top of which are two dipole magnets stuck together under a sheet of white paper with iron filings sprinkled on top to show the magnetic field lines. Also on the optical table: a magnetometer, a multimeter, two small magnets, a forming machine and a bean bag. You know, the stuff you usually find on an optical table. Or not.
Anyway, I did this demo for a TV programme today. It's going to be about the end of the Cassini mission, and the segment features my Big Boss, who does all of the talking. I had originally envisioned a sophisticated demonstration involving a magnetometer and an oscilloscope, and instead I ended up sprinkling iron filings on different permutations of magnets for three hours. ¯\_(ツ)_/¯ C'est la vie!