This thread got me wondering about the demagnetization of ships and submarines. How often is this typically done? Do they have to do it more frequently near the peak of the solar activity cycle, when magnetic storms abound?
per mrAru, retired submariner it is just periodically. The solar magnetic field has nothing to do whatsoever with the magnetic properties of a sub. A sub is roughly 400 - 600 thousand TONS of steel through a saline medium with a lot of mineral content. That causes a significant magnetic field buildup.
They use a wierd formula, distance of travel, time since last degaussing and other factors including where the vessel had been to determine when to go and degausse.
Degaussing is not a frequent occurence. But it will trash out the mag strips on credit cards like you would not believe=)
All the portable computers, all magnetic storage media, the people that remain onboard have to lock up their wallets off the boat to preserve the mag strip data…a major pain in the rump occurrence=)