The SPINlab studies how fluids move within planetary bodies and their atmospheres. Because planets rotate about their axis it can be difficult to predict how liquids, like the outer core of Earth or the dense atmosphere of Jupiter will behave. In comes the SPINlab which uses rotating tanks of liquids to model these effects. You can learn more about the SPINlab and see videos of their experiments at: http://spinlab.ess.ucla.edu
While the SPINlab had a variety of amazing demonstrations (which can be seen on their website!) I volunteered at their Drinkable Planet demonstration. At this booth we were teaching planetary differentiation in a rather unconventional way: with juice!
Every planet in the solar system today has layers, but in the very beginning of the solar system when planets were forming they were a jumble. However, as time passed planets started differentiating (or separating) based on the densities of the different rocks. The densest, heaviest rocks were pulled down by gravity to the center of the Earth while lighter ones stayed on the surface. That's why we have a core made of iron and other heavy metals, a mantle of medium density metals and nonmetals, and a crust of mostly light nonmetals (this is an over simplification!).
Turns our freshly blended juice acts the same way. The juice will sink to the bottom, the pulp will rise to the center, and the frothy foam will float to the top. Armed with two juicers and $200 worth of fruits and vegetables we made fresh juice for hundreds of kids demonstrating how the mixture would separate with time, just like a planet. We then encouraged the kids to watch and see for themselves before drinking their planet.
Setting up the drinkable planet station
A differentiated cup of juice
with light foam on the top, medium pulp in the middle, and heavy juice on the
bottom
