A Wonderleaf question
Why does Uranus spin on its side?
a real page from the book
Uranus probably leans over because, when the solar system was young, a massive icy body, or several of them, crashed into it and changed the direction of its rotation. The planet survived, but its poles ended up aimed far more sideways than any other major planet's.
One lovely clue is its moons: they travel around Uranus in the same tilted plane as the planet's middle. That makes sense if an ancient crash scattered material that later gathered into moons, leaving the whole Uranus system carrying the same sideways memory.
Wonder words
- axis
- collision
- orbit
- equator
Try it out
Spin a ball upright, then gently tap its side and watch how the turning direction changes.
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