Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us all expand our scientific vocabularies together. Today’s term is:
After years of speculation, last September we finally learned the truth. Enceladus, one of Saturn’s moons, has a decoupled crust.
Sorry, Enceladus. I meant no offense. In fact, having a decoupled crust might be a good thing.
We’ve known for some time now that there is liquid water somewhere beneath Enceladus’s surface. Some of that water periodically spurts out of geysers located near the moon’s south pole. You can see this happening in the totally legit Hubble image of Enceladus above.
The big question: how much liquid water is there? Are we talking about a modest subsurface lake near the south pole…
… or does Enceladus have a vast global ocean hidden beneath its surface? You know, the kind of environment that might support life.
By carefully observing Enceladus as it orbits Saturn, astronomers noticed that the moon appears to wobble more than it should. The best explanation for this: the moon’s crust is not attached to anything solid. It floats freely atop a layer of liquid. Enceladus’s crust is—to use the technical term—decoupled from the moon’s rocky interior.
That’s pretty compelling evidence for a global subsurface ocean, and while it doesn’t prove that Enceladus supports life, it does make the possibility a whole lot more likely.
Or does it? Let me check on that for Monday’s post.
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Alternative definition of decouple: to remove any couples from a party or similar social event, leaving all the single gents and ladies free to mingle.