The Strangest Moon In The Solar System
“But the same physics that causes a black car left in the Sun to be much hotter to the touch than a white car in the same conditions is at play on Iapetus, too. When this water attempts to condense, freeze and settle onto the light regions on Iapetus, there’s nothing stopping it. But when it lands on the dark regions, the heat from the surface is enough to sublimate (boil, directly, from a solid phase) the ice, rendering it capable of landing stably and permanently only on the size that isn’t covered in Phoebe’s debris.”
What do you do when you discover a moon around Saturn that’s only visible during half of its orbit? If you’re Giovanni Cassini, you postulate that half of the moon is darker than the other, and you work tirelessly to improve the telescope so that you can see it when it’s in “faint mode.” After more than 3 decades, he succeeded. We now know that Iapetus is not only two-toned, with one side more than 10 times less reflective than the other, but it orbits out of the plane of all the other moons, has a giant equatorial ridge and is unlike any other world in the Solar System. The last of these are mysteries still, but the two-toned conundrum, thanks to Cassini (the NASA mission), has been solved!
Come learn about the strangest moon that we’ve ever found, and its amazing scientific story!