Just floating around…

Published on August 25th, 2011
Just floating around...

The Dead Sea is a pretty mysterious place. At about 400m below sea level it’s the lowest place on Earth’s surface. And the water there is much saltier than normal seawater (it contains about 33 percent salt). Which is why – apart for some really tough bacteria and algae – nothing can live there (that’s where the name comes from). Even boats can’t sail on the surface because they get pushed out of the water and the salt destroys the engines.

But how can a human float on water?
Well, all the salt in the Dead Sea makes the water denser than a human body. And when something is less dense than the liquid its in, it bobs on the surface like a bath-toy. To get a better idea of how this works, try this experiment:

1. Fill two glasses with water.
2. Add six tablespoons of salt to one glass and stir well.
3. Put an egg in each glass.
4. See how the egg sinks in fresh water but floats in saltwater? That’s exactly what happens to your body when you swim in the Dead Sea.

See what it’s like to float on the Dead Sea at http://tinyurl.com/humancork

Pic credit: TSH21

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