十万个为什么·科学阅读30篇（2）

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我们看到的星星是静止的，却感受不到地球自转？

Earth rotates smoothly at about 1670 km/h at the equator, but we don’t feel motion because it’s constant.
Our inner ears detect acceleration — not steady speed — so uniform rotation feels like stillness.
Stars appear fixed because they’re so far away that their apparent movement across the sky is extremely slow.
In reality, Earth’s spin makes stars rise and set, just like the Sun, completing a cycle every 23h56m.
Long-exposure photos reveal star trails — curved arcs proving Earth’s rotation during the exposure.
The Coriolis effect, caused by rotation, deflects winds and ocean currents but isn’t noticeable in daily life.
A Foucault pendulum swings in a fixed plane while Earth turns beneath it, visibly demonstrating rotation.
We only notice Earth’s motion indirectly — through day/night cycles, seasons, and celestial patterns.
Our brains evolved to sense local changes, not planetary-scale inertia or cosmic distances.
That contrast between stillness and motion highlights how perception depends on scale and reference frame.