This week in London, there have been lightning storms in the middle of the night. My partner woke up one morning earlier in the week with a story of how the sky flashed brightly at 2am in quick successions of electricity with no thunder. I slept through the lightning. The sky today is a deep cerulean blue, so deep and bright it feels charged, amplified. I wondered about the residual effects of lightning: what happens to the electromagnetic pulses of energy, the sferics, that are emitted? How far do they travel around earth, and do they return?