Classroom mode

Run it in class

The Moon keeps one face toward us — so is it spinning, or frozen still?

Show of hands — before you project anything

Predict first: if the Moon never spun at all, would we see one side forever, or every side over a month? Why?

  • A Way more than you'd guess
  • B About what you'd guess
  • C Way less than you'd guess

Count the votes out loud. Hold them to it — then watch.

Project it (fullscreen)

Discussion prompts

  • Predict first: if the Moon never spun at all, would we see one side forever, or every side over a month? Why?
  • Predict first: which has to match for one face to stay locked, the Moon's spin speed or its orbit speed, or both together?
  • The lock isn't perfect, we see about 59% of the Moon, not 50%. What kind of wobble could let us peek a little past the edge?

Where it shows up in real life

  • The 'man in the Moon' or 'rabbit in the Moon' pattern, always in the same place every night
  • Walking around a chair while keeping your face toward it, you spin once without noticing
  • The first photos of the Moon's far side, which no one on Earth had ever seen until a spacecraft flew behind it

A prediction-first worksheet — no answer key.

zero prep · no login · any projector

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