This is something that could happen anytime there is a solar storm depending on the details. The solar storm throws off huge amounts of electrically charged par

This is something that could happen anytime there is a solar storm depending on the details. The solar storm throws off huge amounts of electrically charged particles. As these particles hit the Earth, they create electrical currents in the atmosphere (after all, electrical currents are just charged particles moving). Electric currents induce magnetic fields. If the flow is large enough, the magnetic field can be locally much larger than the Earth's thereby canceling the Earth's field out, changing its direction, or even reversing it. This is why compasses can jump around during an auroral storm (during the northern lights). The "crack" in the magnetic field is nothing novel. That cosmic rays were allowed in follows naturally. The (mildly) interesting thing is that it was then detected by this muon tracking telescope.