Sunday, July 15, 2012

SUNSHINE - What You Depend on for Life Can Also Kill You

During the summer of 2011 here in the Texas Hill Country, we experienced a record drought. At one point, the temperature reached over 100F 100 days in a row. Whew! Burn bans. Watering restrictions. And much, much worse for ranchers and farmers. They were selling livestock because their feed sources had dried up.

This summer, though, we've had good rain and the burn bans been lifted. So one weekend I went into the back yard to burn some refuse that was stacking up. Even though it was a hot day, I wore a long-sleeved shirt and a broad-billed hat. Why? To protect myself from solar radiation, which can cause melanomas, a deadly skin cancer.

If you like sporting a tan, it's the easiest thing in the world to get one in Texas. Just go outside and do some chores. Only be careful you don't overexpose yourself!

I don't care about having tanned skin, myself. I'm not sure I understand why so many white people want to have brown skin. A huge portion of the world's population already has brown skin, and it doesn't make them any more or less attractive. If there are space aliens out there studying us, I wonder what they make of all this tanning nonsense...

I've asked around, and people say it makes them look more healthy and attractive. Again, I'm not sure I understand. Do they think people will notice their brown skin and think they've been outdoors a lot getting vigorous exercise? Why not just live a healthy lifestyle and be healthy?

Getting a tan is a big deal with a lot of people. Recently my gym was disrupted with some interior construction. So for a while I was greeted with loud riveting noises, long sheets of black plastic hanging from the ceilings, and a detour to the locker room. I asked one of the employees what it was about, and she told me they were constructing two new tanning rooms. Apparently, there were so many people trying to use the four tanning rooms they already had that they decided to build two more.

There's nothing special about tanning beds that make them safer than exposure to the sun's rays. They put out exactly the same type of energy the sun does, often in more intense doses.

We love sunlight. When it's obscured by clouds for too long, we miss it. But sunlight is only another word for solar radiation. It's deadly. To understand why, consider where it comes from.

Our sun is a medium-sized star (over 100 times larger than Earth), and it's doing what all stars do, only 93 million miles away. It consists of unimaginably hot plasma - millions of degrees hot, interlaced with electromagnetic fields. All this heat comes from the thermonuclear energy released when hydrogen atoms in the sun's core are forced by its massive gravity to fuse into helium atoms. In other words, our star produces the equivalent of millions of hydrogen bombs every second. The sun's gravity keeps this energy from blowing itself apart.

But some of this deadly high-energy radiation escapes the sun's gravity and radiates into space at enormous speed, reaching Earth eight minutes later. The reason life on Earth hasn't been destroyed by this perpetual attack is because most of our star's radiation is deflected by our planet's electromagnetic field and diffused by our atmosphere. On the surface, our eyes sense the visible light portion of the residual radiation. We call what we see "daylight."

We don't see the rest of the spectrum, but it's bombarding us anyway. The energy that makes its way to the surface disturbs the atoms that make up our skin. We sense this excitation as warmth. Stand outdoors on a sunny day with one cheek facing the sun, and this cheek will feel warm while the other remains cool.

The radiation enters the skin and is powerful enough to alter its DNA. If your immune system can't get rid of all the mutations caused by this bombardment, cancers can start growing.

The energy that excites the skin triggers it to produce more melanin, a protective substance which darkens the skin. We call this effect a "suntan." And as I said, white people think this makes them more attractive.

So solar radiation - sunlight - can kill you, but it also gives you life. Radiation from our star is involved in photosynthesis, which sustains plant life, the original source of all our food. Photosynthesis also keeps our atmosphere supplied with oxygen, the vital element in air, which we need for life.

We owe our lives to the sun, but only because most of the sun's deadly radiation is deflected and filtered out before it reaches our back yards, lakes, tennis courts, golf courses and beaches. But if you deliberately expose yourself to this radiation for too long, it can kill you.

My lifelong obsession with wanting to know what's really going on has led me to facts like these. Of course ordinary folks don't think about any of this stuff as they head for the tanning room, happily engaged in this cultural nonsense, completely oblivious to the dangers. Yes, the aliens who study us must find us interesting, indeed.

Post by Dennis E. Coates, Ph.D., Copyright 2012. Building Personal Strength .

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