Earth's got a shifty axis.
One thing we're all taught -- or at least take comfort in believing -- is that the Earth is going to keep on spinning. And, in most ways, it does. After all, it probably would've been in the news if our planet had suddenly grown tired of speeding around the sun and taken a little break.
But a predictably spinning Earth isn't the full story. Turns out, the Earth can shift on its axis should a rather catastrophic activity occur. For instance, the 2011 earthquake in Japan actually moved the Earth's axis about 6.5 inches (17 centimeters) [source: Buis]. What does that mean? Well, reassure the kids that we're not going to fall off the face of the Earth. A shift in the axis only means that the Earth will quaver a bit differently as it rotates, but we aren't all creeping to a different location in space.
Even more likely to cause your child's eyes to go twice their regular size? These shifts in the axis actually caused the Earth's rotation to speed up a bit. That means our days on the planet shortened by about 1.8 microseconds; the days of our lives are going by faster than we thought.