AuroraWatch UK issued a red alert at 14:25 (BST) today based on magnetic field data from the LAN2 (Lancaster) magnetometer. Unfortunately, the readings were spurious and not related to geomagnetic activity. It, instead, appears that some local inteference set off a massive spike in the data (no, it wasn’t the intern!). Whilst we’re not sure yet what this interference was, the magnetometer is located in a site shared with other experiments, and something metallic may have been placed on our instrument or some machine may have been in operation nearby. Investigations will take place and steps to prevent a reoccurence will be taken.
Update: we believe the interference was caused by University staff mowing the grass on a sit-on mower.
http://wp.lancs.ac.uk/aurorawatchuk/2016/08/23/red-alert-cancelled/