Tuesday, 30 October 2012

Our Own Private Storm



In what was a rather less-publicised event than Hurricane Sandy, Bloubosrand in Joburg got hit by an energetic electric storm last night.

In particular, we received one cloud-to-ground strike on a nearby tree -thank you, tree, for taking that one for us - followed a few seconds later by a deadly strike to outside camera number 5.

I think someone else got hit on their property, too: a security alarm went off all night. If I had been a burglar, I would have been delighted, as it clearly indicated that no one was home at all.

The strike to the camera was a bit puzzling at first - we have 2 floodlights, a satellite TV dish and a WiFi Internet antenna on our roof after all, offering much more logical targets - until, about 4 seconds later, I realised that a combination of 3 factors favoured the camera getting hit after all.

Firstly, that's a metal fence it's sitting on. Not just mesh either, but good solid steel. With huge bloody spikes on every paling. The camera was mounted just below one huge bloody spike. When lightning graces the nether regions with its presence, it is looking first and foremost for high charge density, that is the amount of electrically charged particles per volume. Which is really high on a bloody big solid steel spike.
Also the cabling for the camera was wound unprofessionally around the paling.

So - solid metal, sharp point and running electrical current. Sounds like a lightning target to me.

All hail Thor, and thank you for sparing the Internet connection.

Pic: Storm over Sandton