The plasma wind tunnel of the German Aerospace Center (DLR) can simulate the fire-hot conditions of re-entry from the Earth's orbit. The satellite piece was a small magnetic paint, a component that helps in the orientation of a satellite. It contains carbon fibers, polymer composites, copper coils and an iron-cobalt center.
Magnetic motors are one of several satellite components that can withstand full burn-off upon reentry. The magnetic paint finally evaporated mostly at the high temperatures that reached "several thousand degrees Celsius".
The researchers compared the actual results to what they had predicted and found "some discrepancies with the predictive models".
The fiery experiment was part of the ESA Clean Space initiative. Seeing a satellite bit burn is tempting, but it could also help prevent future accidents where debris causes an unwanted return to Earth.