What event likely caused the disappearance of the transient third radiation belt?

Answer

A shockwave from the Sun

The transient third radiation belt that appeared in 2012 existed for about four weeks. Its eventual disappearance is attributed to a shockwave from the Sun that swept through the magnetosphere. This external pressure acted to clear away the trapped particles, returning the magnetosphere to its more typical two-belt configuration.

What event likely caused the disappearance of the transient third radiation belt?

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Discovery - Earth Has 3rd Radiation Belt | Video - YouTube

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