Number ten. The Great Wall of China is the only man-made object visible from space.
To see something on Earth from space, it would have to be pretty big, which the Great Wall of China, all five thousand miles of it certainly is.
But it's only thirty feet across at its widest.
Here's a photo taken from the International Space Station, two hundred miles above Earth.
Can you spot the Great Wall amid the mountain tops? Here, right? No, that's a river.
The Wall is actually here.
Even if you guessed the right lines by pure luck, this photo was taken with a zoom lens, so from the window of the International Space Station, it would look more like this, which pretty clearly makes the Great Wall count as "not visible."
As for the man-made part of this misconception, our glorious man-made cities' blasting lights into the void certainly are visible.
Number nine. Cracking Your Knuckles Causes Arthritis.
Socially obnoxious? Yes. Gives you arthritis later in life as karmic punishment? No.
Number eight. People Only Use Ten Percent of Their Brain.
If you haven't seen a medical drama in the past oh, thirty year, you might not be aware that doctors now have machines that can see inside people's brains.
And contrary to popular belief, ninety percent of the neurons don't sit around all day doing nothing.
While scientists don't yet know exactly what each part does, they do know that all the bits matter.
So if you think that someone could scoop out ninety percent of your brain and you'd still be just fine, then perhaps you really only do use ten percent of it.
Number seven. Eskimos Have Hundreds of Words for Snow.
This one is technically correct but misleading.
Some languages, such as German, like to make compound words by running several smaller ones together, which is why German words are sometimes absurdly long.
Inuit languages use compound words as well. So rather than say "yellow snow" as you would in English, an Inuit speaker combines the two words into one, but it's not really a new word, just a quirk of grammar.
So technically Eskimos do have hundreds of ways to describe snow, but then so does every language.
Number six. You Need Eight Glasses of Water a Day.
While doubtless some people would benefit from drinking more water and drinking less crap, there's no scientific evidence that eight glasses of water a day is the required amount, and some evidence says that it might be too much. And while we're talking about water...
Number five. Tap Water is Bad but Bottled Water is Good.
If you live in a paradise, free from Government regulations like, say, Somalia, then you might have a good reason to prefer bottled water over tap.
But modern, functioning countries have something called health regulations, which cover both kinds of water.
Also, water is extremely dense, making transporting it from those pristine mountain tops and glaciers enormously expensive, which is why bottled water companies don't bother.
"Bottled" water is often just local tap water with a fancy label and an enormous markup.
Number four. Gum Takes Seven Years to Pass Through Your Digestive system.
This is pretty easy to disprove yourself, but it's understandable why most people don't try the experiment
Number three. Blood in your Veins is Blue.
The idea here is that the blood in veins is blue, and it only turns red when exposed to the oxygen in the air.
Thinking this isn't unreasonable, after all, your veins look blue, and medical diagrams show arteries as red and veins as blue, but it's the same mistake as thinking that Mountain Dew is green because it's in a green bottle.
Pour it out and you discover that Mountain Dew is really piss yellow, which is probably why it's in a green bottle to begin with.
The next time you get blood withdrawn from a vein, take a look. What color is it? Red.
How much oxygen is inside a good syringe? None.
Unless you're a Horseshoe crab or Plavalaguna, your blood isn't blue.
Number two. Fan Death.
This misconception is a specialty of South Korea.
Here the belief is that if you spend too much time with a rotating fan in a confined space, it will use up all your oxygen and you'll asphyxiate to death.
Exactly how the fan made of lifeless, anaerobic plastic, competes for your oxygen is unclear, but hilariously South Korea fan manufacturers(who surely must know better) include timers on fans to prevent them from running too long.
Number one. People Swallow Eight Spiders a Year While Sleeping.
Supposedly while you're in bed, helplessly unconscious with your gob wide open, each year eight spiders find their way into your mouth, and you reflexively swallow them.
This is plainly ridiculous.
Spiders love warm, moist places, so eight is far too low an estimate.
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