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Capt. Chiljean

Each year, I seem to get more and more requests for a very special souvenir from the bottom of the Ocean; a 10 ounce styrofoam cup taken down by the mini-research submarine ALVIN and shrunken to 1/8 it's original size by the tremendous pressure. (See comparison photo below)

Let me explain....

The shrinking of a styrofoam cup is actually a fairly simple process. I decorate the cups with waterproof markers before they go on ALVIN. I usually include the dive number, the date, the Latitude and Longitude of the dive, and the depth that ALVIN will be diving. I draw a small sketch of ALVIN and then sign my name on the inside of the cup.

I then place the decorated cups in a large mesh bag, about the size of a pillow case, and tie a knot at the top so they won’t float out. Then, on the morning of the dive, the bag is attached with a tie wrap to the outside of the sub under one of the “skins”.

As ALVIN descends to the sea floor, the pressure increases, and slowly sucks the air out of the styrofoam material. The pressure can be as much as 6000 lb/sq. inch at a depth of 4500 meters. That kind of pressure is hard to imagine, but the shrunken cup is visual proof of this intense pressure.

We think the cups shrink to their full amount in the first 300-400 meters of the surface, so it doesn’t really matter if it’s a 1000 meter dive or a 4500 meter dive. It would shrink to the same size. Due to an occasional imperfection in the styrofoam, some cups shrink differently than others. During the Christmas season I decorate the cup upside-down so it could hang as a tree ornament. My most famous cup is probably the one that landed on the deck of the TITANIC in 1986.

There are many “souvenirs”  that can be recovered by scientists while diving on the sea floor with ALVIN, but none are considered quite as unique as the styrofoam cup shrunken during an ALVIN dive.

I have a few extra shrunken cups. If you'd like to receive one, send me an email.

(I would only ask that you pay for the postage and handling.)