We found this on the beach last week. What is it, and why does it look this way?


This is an ordinary helium balloon, just as you would get for a party. The way that the rubber is evenly shredded tells us how this balloon popped. As a balloon rises, the air pressure around it decreases. With more pressure pushing outwards than inwards, the balloon expands. As it rises higher and higher, it expands more and more, until finally it pops.

A balloon that pops because of a sharp object or a weak spot in the rubber will leave large pieces of rubber, but one that has popped because of low surrounding pressure will shred, just as this one did.

Because it resembles a jellyfish, it is very dangerous. Sea creatures, especially sea turtles, try to eat them and choke to death.

By the way, we picked it up, and put it in the trash.