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Space & science

Venus finishes a year before it finishes one spin.

Venus rotates once in about 243 Earth days and orbits the Sun in 225. Rotation here is measured against the stars—not sunrise to sunrise.

The idea

A striking comparison only works when you know what each unit measures.

An example

The two clocks measure different motions: turning around an axis and traveling around the Sun. A classroom model could turn a small ball while moving it around a lamp to represent those distinct motions; the model need not reproduce their timing.

Try it

Explain why the rotation period and the sunrise-to-sunrise interval should not be treated as interchangeable here.

More context

Venus takes about 243 Earth days to rotate once and about 225 to orbit the Sun. Here “one spin” means rotation relative to the stars, not the interval from one sunrise to the next. Astronomy · approximate durations

Sources & further reading

the 102 platform

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