What is Buoyancy?

Buoyancy is the upward force that keeps an object afloat. This video shows how an object floats in fluid at a level where the weight of fluid displaced is the same as the weight of the object itself.



Floating stone fountains shoot water up under the stone at high pressure to create a stunning effect.



Here's another great explanation of buoyancy with a simple experiment you can try at home using clay and water.

The Great Pacific Garbage Patch--Plastic in the Ocean. Why Should You Care?

Ever heard of the Great Pacific Garbage Patch? It's a place way out in the Pacific Ocean, about as far from human contact as any place on earth, and the water there has collected so much plastic debris that it's turned into "plastic soup." It is estimated to be twice the size of Texas.

Captain Charles Moore is a sailor and researcher who noticed the patch on his return from a Hawaiian yacht race in 1997 and has since dedicated his life to studying plastic in oceans and educating people about the need to stop the pollution.

Researchers have found that the concentration of persistent organic pollutants (POPs) on the surface of small plastic particles called "nurdles" can be up to one million times the level in the ambient seawater. Nurdles--which resemble fish eggs--are regularly consumed by marine animals, posing a considerable threat of choking and intestinal blockage. Furthermore, those highly concentrated POPs are believed to move up the food chain from marine animals into the bodies of humans.

Learn more about oceanic micro-plastic pollution and plastic debris research at the Algalita Marine Research Foundation website.



The Garbage Patch was also featured in 2003 on This American Life's Episode 253: The Middle of Nowhere.