swimming

Silent Lightning

Silent Lightning

Lightning is silent, I think, because we say that it’s the thunder we hear (up to 12 or so miles away). But the two go hand in hand obviously. Lightning is becoming more silent due to the digital age. What that means is that our digital tv‘s don’t crackle with static and our radios are becoming more and more digital so it’s hard to tune in static or hear it anymore. Why is that? Our new technology is designed to interpret 1’s and 0’s so the various frequencies of sounds that would make the static in our old tv’s and radios…..is not detected in our new gadgets. Maybe lightning needs a digital upgrade.

Lightning occurs somewhere on this earth about 8 billion times a day. More lightning occurs when the weather is warmer so when it’s winter in the northern hemisphere our neighbors to the south get their share and the ones in the middle, they don’t get much of a break. We know where lightning is occurring practically instantaneously because we have satellites that detect subtle changes in the atmosphere.  Even during the daytime these satellites apparently are good at detecting lightning 90% of the time including cloud to cloud and intracloud lightning.

I was reading a story about Ben Franklin and his debate with Royal Society members on whether his lightning rods were designed properly and if they did reduce the chance of lightning by defusing the atmosphere. It turns out that we can’t defuse the atmosphere and that long lightning rods are not necessarily better than short one foot ones. Gathering data about lightning strikes back then meant asking “respected” people what they might have witnessed. Even though the lightning rods we have now are very effective, interestingly, most typical houses don’t have lightning rods. They are found on more valuable structures. And many times these rods are hard to find because they can be blended into the structure.

What I really wanted to know about lightning though is how likely is a person in a swimming pool to be hurt by lightning. This would be a dangerous experiment because we’ve probably all read about someone being injured or dying from a lightning strike and we know that water conducts electricity. What I read from two different places on the internet is that a 20 foot distance would be needed and the other source said 200 feet. Since it’s easy to get out of the pool, that’s the best solution and getting out of indoor pools as well because plumbing could carry the electrical discharge into a pool. But apparently pools are unlikely to be hit by lightning since lightning likes taller structures. Still, easier to get out of pool than to depend on lightning hitting the lifeguard stand.

Most of us probably know about the method to calculate how far lightning is from us. Since sounds travels slower than light, it takes 4 –  5 seconds for thunder to travel a mile after you see the flash (flash to bang). The lifeguard association recommends swimmers exit the pool when lightning is 10 miles away. That’s maybe 40 seconds at the quickest to get out of the pool. I don’t recall being that cautious when I was a lifeguard. Better safe than sorry though, right? If you disagree with the lifeguard, find another pool to take your chances.

Here are a couple of interesting things about lightning. It’s thickness is less than a half dollar coin but the length can be 3 miles long and there’s an interesting type of lightning called red sprite lightning which can occur above the clouds. See the link below for some cool pictures of that.

www.universetoday.com/96984/on-the-hunt-for-high-speed-sprites/

red sprite lightning

red sprite lightning

 

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Orthokeratology, why not?

Orthokeratology, why not?

Since I wrote about swimming and I am an optometrist, I have a little passion that I have to write about. I first heard about orthokeratology before I entered optometry school (and I’ll tell you more about that in a sec). Basically I design unique gas permeable contact lenses that a patient sleeps in to correct their vision. That’s all it is….a hard lens that is made for that person’s eye and their prescription and they only wear the lens when they’re sleeping. Say what?

So, back to when I was entering optometry school, I mentioned that to a professor I hadn’t met before. She was showing us around the school on the first day. I thought I would impress her by mentioning this procedure and I still remember who I said it to. Four years later, after graduating, you know how much I learned about orthokeratology? Nada. I still can’t figure out why that is. All that I learned about orthokeratology came after I graduated. You might not follow exactly what I’m saying but if you go to school to learn how to turn a nut, don’t you think the school will show you all the ways how to do that?

Let me tell you briefly about orthokeratology a teeny bit more. After a patient sleeps in the specially designed lenses and removes them in the morning, their vision should be as clear as when they wore glasses or regular contact lenses, or as close if not better. You won’t hear about this procedure from most optometrists. Why is that? Well, as I said in the above paragraph, optometry schools mostly left this cool procedure out of the curriculum. No one at my school, or probably the other optometry schools, shows students what it is and how to do it! Ludicrous!

My first sentence above mentioned swimming. I am a swimmer. Fortunately I don’t have to wear any correction. Yeah, one of those lucky ones you might think. But, in sports like swimming, athletes will probably be wearing soft contact lenses. For children that means they are in the pool or playing soccer or whatever, and have these little pieces of plastic floating on their eyes. If they were doing orthokeratology, their eyes would be free of any glasses or contact lenses when they’re playing and orthokeratology isn’t just for sports, the procedure can be for just about anyone!

I could go on and on about orthokeratology but I’m going to lead you to an association of doctors that provide this service. You can contact me as well 🙂

The Orthokeratology Association of Americaorthosite